Prime Minister Stephen Harper welcomed his Italian counterpart, Enrico Letta, to Ottawa this morning, and the two are likely to discuss trade between Canada and the European Union, as well as the ongoing crisis in Syria.

Harper and Letta both spoke at a dinner in Toronto on Sunday night that was hosted by the National Congress of Italian Canadians, and were to get together more formally Monday for a morning meeting, followed by a working lunch.

Harper and Letta were expected to discuss trade, in particular talks dragging on over a Canada-EU trade agreement. Italy is Canada's 10th largest trading partner, with total exchanges between the two countries amounting to $6.9 billion last year.

They'll also discuss investment and security, including the war in Syria.

Security and terrorism were the subject of questions by reporters, who asked about an attack by al-Shabaab militants at a mall in Kenya that killed two Canadians.

There are reports about an al-Shabaab Twitter account that claimed a Canadian was one of the militants involved in the Kenyan attack. That account was later shut down. 

CBC News has not been able to confirm the validity of the account, and several sources have raised suspicions about its accuracy. 

Harper called the attack "brutal and cowardly."

"We will obviously work with the authorities in Kenya and our partners around the world to do what we can to hold those who have perpetrated this responsible," Harper said.

Khadr convicted of 'heinous' acts

Harper said Canada works around the world with countries vulnerable to terror attacks.

To the report that one of the militants is Canadian, Harper said he wouldn't comment about national security operations.

Enrico Letta and Stephen Harper 20130922

Italian Prime Minister Enrico Letta, left, was honored at a dinner with Prime Minister Stephen Harper Sunday Vaughan, Ont. (Chris Young/Canadian Press)

"We obviously monitor developments very carefully, we exchange information on the travel and activities of persons of interest all around the world. And I'd point out specific actions to deal with this particular phenomenon coming out of Somalia," he said.

"Our government is the government that listed al-Shabaab as a terrorist entity. We did that in 2010. And we have also passed a law to make it specifically a criminal offence to go outside of Canada for the purpose of terrorist training."

Harper said he isn't worried about a mass phenomenon of radicalized Canadians.

Asked about Omar Khadr, a Canadian convicted of war crimes by a U.S. military tribunal, Harper said the government would fight any attempt in court to lessen his punishment. Khadr is in an Edmonton court today asking to be moved to a lower-security prison.

"This is an individual who, as you know, plead guilty, was convicted of very serious crimes including murder, and it is very important that we continue to vigorously defend against any attempts in court to lessen his punishment for these heinous acts," Harper said.

"But we will continue to do anything in our power to empower our police and security forces to deal with these security threats and to work with the international community in identifying these, because they are inevitably cross-border in nature."

Letta arrived on Parliament Hill shortly after 10 a.m. ET. The two prime ministers met in Harper's Parliament Hill office at 10:35 a.m.

Letta, who was elected earlier this year, is on his first visit to Canada. It marks the first official visit of an Italian prime minister since 2001, according to a release from Harper's office. The two leaders last met at the G8 Summit in Lough Erne, Northern Ireland, in June.