WASHINGTON — President Barack Obama said Friday he is releasing an additional $70 million in military aid for Israel, a previously announced move that appeared timed to upstage Republican rival Mitt Romney's trip to Israel this weekend.

The stepped-up U.S. aid, first announced in May, will go to help Israel expand production of a short-range rocket defense system. The system, known as Iron Dome, has proved successful at stopping rocket attacks fired at Israeli civilians from close range, including from Gaza.

Obama announced the new military assistance as he signed a bill in the Oval Office expanding military and civilian cooperation with Israel.

As he sought to underscore his commitment to Israel, the president first said the increased aid totaled $70 million, then said the number was actually $70 billion, even though the smaller figure is correct.

Obama said the bill underscores the United States' "unshakable commitment to Israel."

The White House focus on Israel this week comes as Romney prepares to visit Jerusalem. The presumptive GOP nominee is a critic of Obama's policy toward Israel and has promised to ramp up U.S. aid to the Jewish state, although Obama officials say the administration already provides record levels of funding.

A Romney spokeswoman said the former Massachusetts governor was happy to see steps being taken to enhance security cooperation with Israel.

"Unfortunately this bill does nothing to address yesterday's evasiveness from the White House on whether President Obama recognizes Jerusalem as the capital of Israel, which raised doubt about the president's commitment to our closest ally in the region," said Romney spokeswoman Amanda Henneberg.

Romney is in London on the first leg of an overseas trip designed to burnish his foreign policy credentials.

The White House subtly injected itself into Romney's trip on Thursday after Romney caused a stir by calling London's problems with Olympics preparation "disconcerting."

White House spokesman Jay Carney said Obama "has the utmost confidence" in Britain's ability to host the games.

Obama planned to continue competing with Romney for attention during the opening ceremonies of the Olympic Games, which Romney was scheduled to attend while in London. Romney led the organizing committee for the 2002 Olympics in Salt Lake City.

The Obama campaign was airing an ad for American audiences during the opening ceremonies featuring Obama promoting his middle-class political pitch.

"I believe that the way you grow the economy is from the middle out," Obama says in the ad, echoing a standard campaign refrain. "I believe in fighting for the middle class because if they are prospering, all of us will prosper."

With the ad, Obama guarantees himself a presence during opening ceremonies despite the free media Romney might get by being there in person.

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  • Adam Jentleson

  • Gov. Bobby Jindal (R-La.)

    "We're not worried about overseas headlines. We're worried about voters back here at home in America," Jindal said on a conference call with reporters Thursday.

  • Channel 4 News in London

    Felicity Spector of Channel 4 News in London <a href="http://www.channel4.com/news/london-calling-mitt-romneys-golden-gaffe-in-olympics-visit" target="_hplink">writes</a> that Romney has undertaken "a charm offensive, that has proved rather more offensive, than charming."

  • Austan Goolsbee

  • UK Prime Minister David Cameron

    In response to Romney <a href="http://2012.talkingpointsmemo.com/2012/07/romney-london-olympics-david-cameron.php" target="_hplink">questioning</a> whether London could handle the security issues ahead of the summer games, Cameron retorted that he had no doubt "Britain can deliver." "We are holding an Olympic Games in one of the busiest, most active, bustling cities anywhere in the world," Cameron said. "Of course it's easier if you hold an Olympic Games in the middle of nowhere."

  • The Sun

    The <a href="http://www.scribblelive.com/Event/SinglePost.aspx?PostId=35975791" target="_hplink">tabloid</a> said Romney's visit was "not a great day at the office."

  • JONATHAN HAYNES TWEET, TOO

  • The Times of London

    The daily paper called Cameron's comment an "Olympic putdown" in an above-the-scroll <a href="http://2012.talkingpointsmemo.com/2012/07/romney-london-olympics-gaffes.php" target="_hplink">headline</a> online.

  • JANICE TURNER TWEET TOO!

  • The Telegraph

    "If Mitt Romney doesn't like us, we shouldn't care," <a href="http://www.telegraph.co.uk/news/worldnews/mitt-romney/9428764/Commentary-if-Mitt-Romney-doesnt-like-us-we-shouldnt-care.html" target="_hplink">writes</a> the paper.

  • The Daily Mail

    The newspaper <a href="http://www.dailymail.co.uk/news/article-2179309/Mayor-Boris-Johnson-attacking-Mitt-Romney-Olympic-torch-arrives-London.html" target="_hplink">called</a> the start of Romney's trip "humiliating."

  • The London Evening Standard

    The newspaper <a href="linkgoeshere" target="_hplink">wrote</a> "David Cameron slaps down US presidential hopeful Mitt Romney over Games gaffe."

  • BBC

    "Mr Romney is credited with rescuing the 2002 Winter Games in Salt Lake City, now he's appeared to question London's readiness to host a successful olympics," host George Alagiah <a href="http://2012.talkingpointsmemo.com/2012/07/romney-london-olympics-gaffes.php" target="_hplink">said</a>, adding "If (Romney's) here to make friends, he's got a funny way of showing it."

  • James Chapman