A veterans support group wants Prime Minister Stephen Harper to delay enacting new veteran benefits legislation that was rushed through the Commons last spring with unanimous support.
The group says Bill C-45 takes away more from veterans than it gives them.
Retired soldiers - who point out the bill won't affect their benefits - warned Tuesday that Bill C-45 removes the lifetime disability pension paid to disabled veterans and their survivors.
The pension would be replaced by a one-time lump sum payment.
As well, they say, the bill would remove all income support for disabled veterans after they reach 65 years of age.
Retired Capt. Sean Bruyea says by enacting the law, the federal government is abandoning soldiers serving in Afghanistan and other conflict zones.
Bill Graham, the interim Liberal leader and former defence minister, defended the legislation and appeared nonplussed by the criticism.
"My understanding was in fact at the time that the veterans groups themselves - since they were grandfathered under the previous system - were supportive of the measures that were brought in," Mr. Graham told reporters.
"What it was attempting to do was to change the system so that people, when they had problems, would be better educated ... so they could transit into civilian life. That was the thrust of what was being attempted."
All four leaders of the major federal parties agreed last May to fast-track the legislation through the Commons in order to honour the year of the veteran.
At the time, the new Veterans Charter was described as the most comprehensive modernization of programs and services for vets since the Second World War.
The legislation promised to provide rehabilitation services, health benefits, job placement assistance, economic loss support, disability awards and case management.
The Royal Canadian Legion welcomed the bill when it was introduced in 2004, calling it "a step in the right direction for Canada's veterans, new and old."