Canada's secretary of state for foreign affairs says she cares about the health of an ailing Canadian woman imprisoned in a Mexican jail, but has no authority to bring her home.

"It's a foreign country and she's in a foreign judicial system," Helena Guergis told CTV's Mike Duffy Live on Monday from Yellowknife, N.W.T.

"Canada does not have any control over the government of Mexico or their judicial process. Any suggestion that a politician can influence a judge's decision is completely inappropriate."

Brenda Martin, 51, was transferred to the hospital ward of her prison early Monday and placed under a suicide watch, after a constitutional challenge to her continued imprisonment was denied.

"I care a great deal," said Guergis. "If I could have Ms. Martin home I would."

Debra Tieleman, a friend of Martin's, told CTV Newsnet that Martin is in an "extremely fragile" state.

"She fluctuates between being extremely withdrawn ... to begging and pleading for somebody, anybody, to please help her," she said.

"Mentally, she's really a mess ... I don't know how much more of this she can take."

Martin, a native of Trenton, Ont., has been in a Mexican prison for two years.

She has been jailed in connection with a fraud carried out by former boss Alyn Richard Waage, an inmate in a U.S. prison.

Martin has proclaimed her innocence and Waage backs that claim. Although Martin has been charged with money laundering, she has not yet been tried or convicted.

"The Mexican government considers this to be a very serious charge and there is no bail, which is why she's been in jail," said Guergis.

On Monday, a judge decided Martin's case would proceed to a criminal trial.

Martin worked for Waage as a chef for 10 months, before she was fired and offered a severance package. She then opened her own catering business.

After Waage was arrested and convicted of running a major Internet pyramid scheme, Martin was taken to prison in February 2006. Authorities alleged that her severance package was actually money she'd been given to launder.

Tieleman said Martin was initially interrogated by "federales (federal police) without benefit of either a lawyer or interpreter." That claim was the focus of Martin's constitutional challenge to have her charges dismissed.

She also said Martin is wondering if the Canadian government will write a formal diplomatic note of protest to the Mexican government.

"In that note, it would lay out where Brenda's rights have been abused under the international treaty that Canada and Mexico are both signatories on," she said.

Any such note would likely come from Guergis, according to CTV's Graham Richardson.

Guergis said she has worked hard to ensure the Mexican government "is aware that we have concerns about the length of time Ms. Martin's trial has taken."

She also said she met with the Mexican ambassador last Friday to discuss the case.

Liberal MP Dan McTeague has been hammering the government's handling of the Martin affair, saying officials have done little to help Martin.