TEHRAN, Iran — Iran sought Sunday to calm hard-liners worried over groundbreaking exchanges with Washington, saying a single phone conversation between the American and Iranian presidents is not a sign that relations will be quickly restored.

The comments by Deputy Foreign Minister Abbas Araghchi appeared tailored to address Iranian factions, including the powerful Revolutionary Guard, that have grown uneasy over fast-paced outreach last week between the White House and President Hassan Rouhani, which was capped by a 15-minute phone call with President Barack Obama.

"Definitely, a history of high tensions between Tehran and Washington will not go back to normal relations due to a phone call, meeting or negotiation," Araghchi was quoted by the semi-official Fars news agency as saying.

Rouhani seeks to restart stalled talks over its nuclear program in the hopes of easing U.S.-led sanctions. Iran, however, has not clarified what concessions it is willing to make with its nuclear program in exchange.

Araghchi also reiterated statements by Iran's Supreme Leader Ayatollah Ali Khamenei, who said he no longer opposes direct talks with Washington but is not optimistic about the potential outcome. Khamenei appears to have given Rouhani authority to handle the nuclear talks with world powers, scheduled to resume in Geneva in two weeks, and seek possible broader contacts with the Obama administration.

"We never trust America 100 percent," said Araghchi. "And, in the future, we will remain on the same path. We will never trust them 100 percent."

The divisions over Rouhani's overtures were on display Saturday when he returned from New York. Supporters welcomed him with cheers, but a smaller pocket of protesters shouted insults.

The U.S. and Iran broke ties after the 1979 Islamic Revolution when mobs stormed the U.S. Embassy in Tehran. A total of 52 hostages were held for 444 days.

A hard-line lawmaker, Hamid Rasaei, criticized the phone call as "breaking the resistance brand" of Iran – a reference to the self-promoted idea that Iran is the anchor for opposition to Israel and Western influence in the region.

He said acceptance of Obama's phone call by Rouhani was "undignified" and allowed the U.S. to claim Iran seeks to modify its policies.

"You converted a win-lose game to a win-win one" for the U.S., he said during a parliament session Sunday.

Another conservative lawmaker, Alaeddin Boroujerdi, head of the influential parliamentary committee, saw the phone call as Rouhani trying to help the "failing reputation" of Obama.

Later on Sunday, Rouhani seemed to defend the cautious openings with Washington in comments on his presidential website, saying his "administration is faithful to change in foreign ties, which is a national demand."

The core of the opposition to Rouhani appears built around supporters of former President Mahmoud Ahmadinejad, who once sent a letter to then-President George W. Bush in an attempt to open dialogue. Ahmadinejad apparently was rebuffed by Bush, and the former president later fell from favor with Khamenei after trying to challenge his authority.

Khamenei's presumed nod to Rouhani to test outreach with Washington may be seen by Ahmadinejad's backers as another slap to the former president.

Ahmadinejad's first public comments on the Obama phone call carried a noncommittal tone. "I don't know, maybe it was the right thing to do," the conservative Baztab news website reported him as saying Sunday.

On the flip side, the phone call brought jokes circulating in Iran by text message.

"I know Rouhani called Obama first," read one. "Then Obama told him, `It's better that I call you since you are under sanctions and your call may cost a lot.'"

Earlier on HuffPost:

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  • Iranians celebrate the victory of moderate presidential candidate Hassan Rouhani (portrait) in the presidential elections at Vanak square in northern Tehran on June 15, 2013. Iranian Interior Minister Mohammad Mostafa Najjar said Rouhani won outright with 18.6 million votes, or 50.68 percent. (ATTA KENARE/AFP/Getty Images)

  • Passengers in a public bus flash victory signs in a reaction of supporters of the Iranian presidential candidate Hassan Rouhani, as they attend a celebration gathering, in Tehran, Iran, Saturday, June 15, 2013. (AP Photo/Vahid Salemi)

  • A supporter of Iranian presidential candidate Hassan Rouhani, shown in poster, attends a celebration gathering in Tehran, Iran, Saturday, June 15, 2013. (AP Photo/Vahid Salemi)

  • Supporters of the Iranian presidential candidate Hassan Rouhani, shown in poster at center, attend a celebration gathering in Tehran, Iran, Saturday, June 15, 2013. (AP Photo/Vahid Salemi)

  • A female supporter of Iranian presidential candidate Hassan Rouhani flashes a victory sign as she holds his poster during a celebration gathering in Tehran, Iran, Saturday, June 15, 2013. (AP Photo/Vahid Salemi)

  • Supporter of the Iranian presidential candidate Hassan Rouhani celebrate outside his campaign headquarters in Tehran, Iran, Saturday, June 15, 2013. (AP Photo/Vahid Salemi)

  • A female supporter of Iranian presidential candidate Hassan Rouhani, flashes a victory sign as she holds his poster during a celebration gathering in Tehran, Iran, Saturday, June 15, 2013. (AP Photo/Vahid Salemi)

  • A supporter of Iranian presidential candidate Hassan Rouhani holds his poster as another youth waves to a clergyman outside the campaign headquarters of Rouhani, in Tehran, a day after the election, Iran, Saturday, June 15, 2013. (AP Photo/Vahid Salemi)

  • An Iranian woman flashes the sign for victory as she holds a portrait of moderate presidential candidate Hassan Rouhani during celebrations for his victory in the Islamic Republic's presidential elections in downtown Tehran on June 15, 2013. (BEHROUZ MEHRI/AFP/Getty Images)

  • Iranians supporters of moderate presidential candidate, Hassan Rouhani flash the sign of victory holding a portrait of him as they wait for the final results outside his campaign headquarter in downtown Tehran on June 15, 2013. Rouhani has a clear lead in Iran's presidential election, garnering 51 percent of the vote at 65 percent of polling stations across the country, the interior ministry said. (BEHROUZ MEHRI/AFP/Getty Images)

  • An Iranian woman holds a portrait of moderate presidential candidate Hassan Rouhani as she rides on a motorcycle along Valiasr street in Tehran on June 15, 2013 after he was elected as president. (BEHROUZ MEHRI/AFP/Getty Images)

  • An Iranian woman holds her purple scarf, the campaign color of moderate presidential candidate Hassan Rouhani, as she celebrates along Valiasr street after he was elected as president on June 15, 2013, in the capital Tehran. (BEHROUZ MEHRI/AFP/Getty Images)

  • Iranians gather as they celebrate the victory of moderate presidential candidate Hassan Rouhaniin the presidential elections at Vanak Square, in northern Tehran, on June 15, 2013. Iranian Interior Minister Mohammad Mostafa Najjar said Rouhani won outright with 18.6 million votes, or 50.68 percent. (ATTA KENARE/AFP/Getty Images)

  • Iranian supporters of moderate presidential candidate Hassan Rouhani who won the national elections, celebrate in downtown Tehran on June 15, 2013. (BEHROUZ MEHRI/AFP/Getty Images)

  • Iranians celebrate along Valiasr street, in the capital Tehran, on June 15, 2013, after moderate presidential candidate Hassan Rouhani was elected as president. (BEHROUZ MEHRI/AFP/Getty Images)

  • An Iranian woman celebrates the victory of moderate presidential candidate Hassan Rouhani (portrait) in the presidential elections at Vanak Square, in northern Tehran, on June 15, 2013. (ATTA KENARE/AFP/Getty Images)

  • Iranians celebrate the victory of moderate presidential candidate Hassan Rouhani (portrait) in the Islamic Republic's presidential elections at Vanak Square, in northern Tehran, on June 15, 2013. (ATTA KENARE/AFP/Getty Images)

  • Iranians celebrate the victory of moderate presidential candidate Hassan Rouhani (portrait) in the presidential elections at Vanak Square, in northern Tehran, on June 15, 2013. (ATTA KENARE/AFP/Getty Images)

  • Iranians gather to celebrate the victory of moderate presidential candidate Hassan Rouhani in the presidential elections at Vanak Square, in northern Tehran, on June 15, 2013. (ATTA KENARE/AFP/Getty Images)

  • An Iranian woman celebrates the victory of moderate presidential candidate Hassan Rouhani in the presidential elections at Vanak Square, in northern Tehran, on June 15, 2013. (ATTA KENARE/AFP/Getty Images)

  • Iranians gather as they celebrate the victory of moderate presidential candidate Hassan Rouhani in the presidential elections at Vanak Square, in northern Tehran, on June 15, 2013. (ATTA KENARE/AFP/Getty Images)

  • Iranian women hold a portrait of moderate presidential candidate Hassan Rouhani who won the national election in downtown Tehran on June 15, 2013. (BEHROUZ MEHRI/AFP/Getty Images)

  • A female supporter of Iranian presidential candidate Hasan Rouhani flashes a victory sign, as she holds his poster, during a celebration gathering, in Tehran, Iran, Saturday, June 15, 2013. (AP Photo/Vahid Salemi)

  • Iranians celebrate the victory of moderate presidential candidate Hassan Rowhani (portrait) in the Islamic Republic's presidential elections in downtown Tehran on June 15, 2013. (BEHROUZ MEHRI/AFP/Getty Images)

  • In front of a portrait of the late Iranian revolutionary founder Ayatollah Khomeini, presidential candidate Hasan Rowhani, a former top nuclear negotiator, center, gestures to his supporters at a rally in Tehran, Iran, Saturday, June 1, 2013. (AP Photo/Ebrahim Noroozi, File)

  • An Iranian woman holds a portrait of moderate presidential candidate Hassan Rouhani as she rides on a motorcycle along Valiasr street in Tehran on June 15, 2013 after he was elected as president. (BEHROUZ MEHRI/AFP/Getty Images)

  • Iranians celebrate the victory of moderate presidential candidate Hassan Rouhani in the Islamic Republic's presidential elections at Vanak square in northern Tehran on June 15, 2013. (ATTA KENARE/AFP/Getty Images)

  • Iranians celebrate the victory of moderate presidential candidate Hassan Rowhani (portrait) in the Islamic Republic's presidential elections at Vanak square in northern Tehran on June 15, 2013. (ATTA KENARE/AFP/Getty Images)