A Somali man has been sentenced to 15 years in jail for his role in the kidnapping of a Canadian journalist in Somalia, according to Canadian media.

Ali Omar Ader, 40, was found guilty in December on a charge of hostage-taking charge for his involvement as a negotiator in the kidnapping.

Ader was arrested in Ottawa in 2015 by the Royal Canadian Mounted Police.

Amanda Lindhout and Australian photojournalist Nigel Brennan were taken hostage near Mogadishu in 2008.

The sentence was handed down on Monday in an Ontario Superior Court.

During his trial, prosecutors claimed that Ader was the primary negotiator for the militants who captured the pair.

Ader repeatedly pressed Ms Lindhout and Mr Brennan's families for ransom money, the court heard.

It was eventually paid.

Ms Lindhout and Mr Brennan were taken hostage at gunpoint while working on a story about displaced persons camps near the Somali capital.

They were held captive by an unidentified militant group for 460 days before being released in November 2009.

They have described having been brutally assaulted, tortured, and nearly starved during their captivity.

The kidnapping of the two journalists and their eventual release was covered by media worldwide.

In 2013, Ms Lindhout co-wrote a bestselling memoir about her experience as a captive, and she regularly delivers speeches around the world on her experience and on related issues like living with post-traumatic stress disorder.

Almost seven years after the pair's release, RCMP investigators managed to lure Ader to Canada under the pretence of signing a publishing contract for a book on Somalia's history.

It was the culmination of a lengthy international undercover operation.

As Mr Brennan is not a Canadian citizen, Ader did not face any charges in Canada related to his kidnapping.

But the photographer did give his victim impact statement in court - later posted online - where he asked the judge to show Ader clemency.

"I believe that forgiveness is the one thing that will keep humanity moving forward," he said.