A Canadian who says he fought alongside Kurdish forces against ISIS in Syria tells CBC News that he will be deported from Australia, where he was detained earlier this week as he was trying to enter the country.

Robert Somerville, who is originally from Sooke, B.C., is a Canadian veteran who fought in Afghanistan. He says he spent six months fighting ISIS alongside the YPG, a Syrian Kurdish militant group.

He said he was granted an Australian visa, which he applied for after being deported from Iraq for one year. Somerville said he was deported because he "pissed off" an official when he was applying for a visa to stay in Iraq. Somerville said he forgot to bring some forms and a photocopy of his passport.

"So he was pissed, so he banned me," Somerville told CBC Radio's As It Happens.

Somerville said he wanted to visit Australia to see his father, whom he hadn't seen in 20 years.

"It was winter and I wanted to go somewhere warm. I did my six months … and decided to leave."

Somerville said he also felt he had contributed what he could to the fighting, working as a machine gunner.

"You have five per cent, 10 per cent mind-numbing fear and 90, 95 per cent boredom," he said of his experience in Syria.

Reason for deportation unclear

Upon arrival in Australia, he said he was detained and border services questioned him. Somerville said the reason they gave him for his deportation to Canada was that he had failed to disclose a Kurdish nickname he had received.

He said he was not going to fight the deportation and would likely be leaving within a few hours for the airport.

Australian Border Force and Immigration Department officials did not immediately respond to a request for comment from Reuters.

"The basis for the visa cancellation is at this stage unclear," Somerville's Melbourne-based lawyer, Jessie Smith, told the Australian Broadcasting Corporation. "It may have political undertones and could be contestable."

Australia introduced sweeping security reforms in 2014 over concern at the number of its citizens heading to Iraq and Syria to fight. About 110 Australians are estimated to be involved in the conflict. It is illegal for Australian citizens to support any armed group in Syria, and fighters face life in prison upon return.

The Syrian Kurds have established control over wide areas of northern Syria since the country erupted into civil war in 2011, and the YPG has become a major partner in the U.S.-led coalition against ISIS, militants fighting to establish an Islamist state in Iraq and Syria.

Several foreigners, including Europeans and Americans, have joined the YPG. but their numbers are dwarfed by foreign recruits to the other side. Kurds in Syria and Iraq are backed by a U.S.-led coalition, including Australia, which has been bombing ISIS in both countries.