Embattled Conservative Julian Fantino has been demoted from his position as veterans affairs minister to a junior cabinet role after less than 18 months on the job.

The Prime Minister's Office confirmed the change Monday. The shuffle took place at a swearing-in ceremony at Rideau Hall in Ottawa.

Fantino was demoted to his former position as the associate minister of National Defence, where he will support lead Minister Rob Nicholson in areas of Arctic sovereignty, information technology security and foreign intelligence.

In a statement Monday, Fantino said he was “proud of the critical improvements” the Harper government has delivered to Canadian veterans and their families.

“I will remain forever grateful to the countless veterans I had the distinct honour of meeting in all regions of Canada, and while abroad visiting the cemeteries of those brave men and women who died in service to their country,” said Fantino.

Erin O'Toole, formerly the parliamentary secretary to the minister of international trade, was named the new minister of veterans affairs. O'Toole is also a former member of the Royal Canadian Air Force.

"I am confident that they (Fantino and O'Toole) will deliver results and provide strong leadership as they go about addressing their duties and responsibilities," said Prime Minister Stephen Harper in a statement Monday afternoon.

But the shuffle was met with criticism by the official Opposition and veterans advocates.

At a press conference in Ottawa Monday, NDP Leader Thomas Mulcair called the Fantino firing a "half-hearted firing of an incompetent minister," adding that 2014 was a "terrible year for Fantino." He said it is a "mystery" how Fantino can remain in cabinet

Fantino, who entered politics in a 2010 byelection, was named the minister of veterans affairs in 2013. During his time as minister, the department came under fire from the auditor general, the veterans ombudsman, veterans groups, and the opposition parties.

From jobs cuts to lapsed budget money, to a run-in with an angry wife of a veteran suffering from PTSD, Fantino faced strong criticism for his handling of the file.

Mulcair also congratulated O'Toole on his new role and called on him to reopen the nine regional Veterans Affairs offices the government closed last year. While Mulcair was very critical of Fantino, calling him a "serial problem" for Harper, he blamed the Conservative government for its overall mishandling of the file.

President of Canadians Veterans Advocacy Michael Blais told CTV News Channel he was pleased with Harper's "long-overdue" decision to replace Fantino.

However, he said the group is not impressed with the prime minister’s decision to replace him with O’Toole, who has been speaking on the file in recent months.

"Frankly, unless the message changes, the messenger continues to be irrelevant," said Blais. "He's (O’Toole) a poster boy that Prime Minister Harper can use to say that things are being done differently."

Pat Stogran, Canada's first veterans ombudsman, shrugged off Fantino's demotion, saying "it's just more of the same." Stogran also called O'Toole an "eager beaver" who just covered Fantino's back when he was a parliamentary secretary. 

"I don't hold out any hope at all for Erin O'Toole," said Stogran. "His military service doesn't offer him any more credibility than any of his predecessors." 

Putting the recent shuffle aside, Stogran said the one gesture that would mean the most would be a public inquiry into the workings of Veterans Affairs Canada. 

Speaking to CTV's Power Play, Chris Dupee, founder of Military Minds, said Fantino's demotion was a "political play." He said Fantino has just been a public figure for the veterans affairs file and that the real problem lies "behind the scenes" at the department. 

The Royal Canadian Legion welcomed the announcement of O'Toole appointment as minister, and said it looks forward to meeting with him.

“This is a political move and we will not concern ourselves with the reasons behind it,” says Tom Eagles, Dominion President of The Royal Canadian Legion, in a statement.

"The Legion has great expectations that this government and all political parties will put the past behind and move forward to create an environment where Veterans know that this country’s obligation to care for them when they need it will be met."