Texas senator Ted Cruz drops his Canadian citizenship

Canada-born US senator Ted Cruz has made good on a promise to renounce his birth country's citizenship, amid speculation he could make a run for the White House in 2016.

His spokeswoman, Catherine Frazier, said Cruz's action became official last month and that the Texas senator received written confirmation at his home in Houston on Tuesday. She said the Republican was "pleased to have the process finalised".

Frazier added: "Being a US senator representing Texas, it makes sense he should be only an American citizen."

Cruz, 43, was born in Calgary, Alberta, in 1970, while his parents were working in the oil business there. His mother, Eleanor, is from the US while his father, Rafael, is a Cuban who didn't become a US citizen until 2005.

Though he has been in office only about 18 months, Cruz helped lead last year's partial government shutdown and has become a conservative grass-roots champion.

Amid questions last year about his eligibility to be president should he decide to run, Cruz released his birth certificate to the and said he was surprised to find that he had dual Canadian-US citizenship.