(Adds confirmation that Canadian rules make Cruz a citizen; number of renunciations)
By David Ljunggren
OTTAWA, Aug 20 (Reuters) - U.S. Senator Ted Cruz, who says he recently discovered he is likely a Canadian, must win security clearance from Canada's spy agency, fill out a four-page form and then wait up to eight months to sever his ties to America's northern neighbor.
Cruz, a Texas Republican who has fueled speculation that he may run for president in 2016, was born in Canada, which automatically makes him a citizen. On Monday he offered to renounce that citizenship.
"Nothing against Canada, but I'm an American by birth and as a U.S. senator, I believe I should be only an American," Cruz, a U.S. citizen who grew up in Houston, said in a statement.
Cruz would be in rare company if he goes ahead. Government figures show only 192 people gave up Canadian citizenship last year.
People giving up Canadian citizenship must prove they are or will become a citizen of another country, do not live in Canada and are not a security threat. They must also explain in writing why they do not want to be a Canadian anymore.
A nonrefundable C$100 ($96) fee is payable in advance.
"It's very, very uncommon ... . I've been practicing 26 years and I don't think I've ever seen anybody renounce it," said Guidy Mamann, an immigration lawyer with Toronto law firm Mamann, Sandaluk & Kingwell.
Citizenship and Immigration Canada official Remi Lariviere said reasons for renunciation could include running in a foreign election or serving in a foreign military.
"Currently, under the Citizenship Act, children born in Canada are automatically Canadian citizens, unless they are born to foreign diplomats," Lariviere said. "In some situations, an individual may decide to renounce their Canadian citizenship."
BORN IN CALGARY
As part of the process, the Canadian Security Intelligence Service spy agency must issue a security clearance to anyone who wants to give up their citizenship. Once officials have examined a file and cleared an applicant, it goes to a citizenship judge for a final decision.
Citizenship Canada's website says if someone were to apply now, the process would take about eight months.
Cruz, 42, who released a copy of his birth certificate on Monday, was born in Canada's oil capital Calgary, where his Cuban-born father was working in the energy industry. The lawmaker's mother was born in the United States. He moved to America at age 4.
U.S. President Barack Obama faced intense scrutiny from "birthers" about his eligibility to be president. Born in 1961 to an American mother and Kenyan father, Obama released his birth certificate in 2011, which showed he was born in Hawaii.
Mamann, the lawyer, said that from what he knew of the case, Cruz was definitely a Canadian citizen.
Canada became a haven for U.S. draft dodgers during the Vietnam War after then-Prime Minister Pierre Trudeau expressed sympathy for their plight. Far more Canadians, however, have moved to the United States over the years.
Canadian government statistics show that, over the last decade, the number of permanent residents from the United States peaked at 11,216 in 2008, the year that Obama was elected president for the first time.
($1=$1.04 Canadian) (Additional reporting by Janet Guttsman and Randall Palmer; Editing by Xavier Briand)