In the video campaign, the Public Service Alliance of Canada uses stories of veterans to highlight what it says is the impact of the closure of veterans' services offices in the past two years.
The union argues that the mental-health troubles of veterans are being exacerbated by the fact they can no longer get in-person services in their home towns.
But the campaign is nothing but fear-mongering, Veterans Affairs Minister Erin O'Toole said in a strongly worded letter to PSAC national president Robyn Benson.
"I find the ads to be intentionally misleading," O'Toole wrote in the letter dated Thursday.
"Your public campaign raises an issue regarding nine administrative offices, seeking to mislead veterans, their families and all Canadians into believing their only access for mental health or medical treatments from Veterans Affairs Canada is through a toll-free telephone number," said O'Toole.
"Nowhere do you inform veterans and their families that 27 front-line mental health clinics have been opened or are opening shortly, nor do you mention the 31 new integrated personnel and support centres of Veterans Affairs and the Canadian Armed Forces."
The union is also doing a disservice to its own members who provide services to former soldiers, said O'Toole.
"It seems that you appear comfortable ignoring the good work done by some of your own members for the wider purposes of a political public action campaign."
The union, however, stood by its campaign in its response to O'Toole.
"I am shocked that minister O’Toole would attempt to silence the voices of veterans who are speaking out," Benson said in an email.
"These veterans speak for themselves and continue to do so. They are saying that they feel abandoned because there is no longer a Veterans Affairs office in their communities to walk into and receive immediate and face-to-face access to services."
The federal government has been under fire for some time over cuts at Veterans Affairs.
An auditor general's report late last year said one in five ex-soldiers seeking mental-health care had to wait up to eight months for their application to be reviewed.
Nine regional offices that served veterans were closed by early 2014 despite complaints to former veterans affairs minister Julian Fantino.
But the Conservatives insist that service levels have been increased through delivery of veterans programs at offices that jointly provide other government services.
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