A Toronto man believed to be the only Canadian ever charged under the United Nations Act will remain in custody as he awaits trial for allegedly trying to send nuclear technology to Iran, a judge ruled Monday.

Mahmoud Yadegari, 35, was arrested last month after a joint eight-week investigation by the RCMP and the U.S. Department of Homeland Security. He spent the last two-and-a-half weeks in jail awaiting a decision on his application for bail.

His wife wept after Judge Sheila Ray denied his bid for release.

"Mr. Yadegari is disappointed that he is not being reunited with his wife and young son," his lawyer, Craig Penney, said in a written statement.

Authorities allege Yadegari tried to procure and export pressure transducers. The devices, which are hand-sized, have a myriad of legitimate commercial uses but can also be used in the production of enriched uranium for military purposes.

At a press conference following his arrest, police said Yadegari allegedly purchased 10 of the transducers from a Boston-area company for about $1,100 each. Police said the company alerted authorities after learning the transducers would be shipped to Yadegari in Toronto, and then on to Dubai in the United Arab Emirates before being sent to Iran.

Yadegari allegedly took steps to conceal the purpose of the transducers when he tried to ship them out so they could be sent without the requisite export permits.

Evidence heard during his court hearing and Ray's reasons for denying Yadegari's release cannot be reported under the standard publication ban imposed on bail hearings.

"Today is not the day to meet these allegations, nor can it be done through the media," Penney said in his statement.

"The court process will take months. We ask that you keep an open mind until Mr. Yadegari has an opportunity to answer these allegations in court."

Yadegari is charged under the Customs Act and Export and Import Permits Act, and is also accused of violating United Nations sanctions on Iran.

The UN Security Council banned exports of nuclear-related technology to Iran in 2006 because of alleged efforts to build nuclear weapons.

Yadegari is a Canadian citizen who emigrated from Iran in 1998.

Iran insists it is enriching uranium to produce nuclear energy for civilian purposes, but the United States and some European countries accuse Tehran of secretly seeking to build nuclear weapons.

In February, U.S. President Barack Obama's administration said it would seek to end Iran's nuclear ambition and its support for terrorism.

That drew an immediate rebuke from Iran's envoy to the United Nations, who said Iran has never and will never try to acquire nuclear weapons.