Cruz, 43, recently said in an interview with the Dallas Morning News that lawyers are preparing the paperwork to renounce citizenship, just as he said in August.
Richard Kurland, a Vancouver-based immigration attorney, wonders what's taking so long. Kurland said Friday that unless there's a security or mental health issue that hasn't been disclosed, renouncing citizenship is a simple, quick process.
"If he's attempting to bring our system into disrepute by suggesting it's lengthy and complex, it's just not true. Revocation is one of the fastest processes in our system," said Kurland.
Cruz's office didn't immediately respond for a request for comment.
The thorny issue of the tea party darling's birthplace has been a headache for the senator, since some in the neo-conservative movement had accused President Barack Obama of being born in Kenya and thus not eligible to be U.S. president. Obama's father was Kenyan, his mother American.
Cruz, the junior senator from Texas, is eyeing a run for president in 2016.
Cruz was born in Calgary, Alberta, when his parents were working in the Canadian oil business. His mother, Eleanor, was born in America, while his father, Rafael, is a Cuban who didn't become a U.S. citizen until 2005.
Under U.S. law, a child born to an American parent gets automatic citizenship even if the birthplace is beyond U.S. borders. Canada, like the United States, also gives automatic citizenship to anyone born on its soil.
Cruz has said the news that he possessed dual citizenship came as a surprise to both him and his parents earlier this year. The lawmaker insists his mother was told when he was a child that her boy would have to take affirmative action to claim Canadian citizenship.