The federal Liberals say a new benefit to provide financial support for Canada’s most severely injured veterans in their later years is borne of public pressure and not concern for wounded vets.

The new Retirement Income Security Benefit will provide a monthly income support payment for moderately to severely injured veterans after the age of 65.

Veterans Affairs Minister Erin O'Toole unveiled the proposed new benefit at a press conference in Toronto Monday morning.

In response to the new measure, the Liberals accused the government of taking "years" to offer financial support to severely wounded veterans.

"This action was provoked by public pressure, not concern for those who have served, and only comes after the Prime Minister rejected the sacred obligation to our veterans," Liberal Veterans Affairs critic, Frank Valeriote, said in a statement.

"As the Veterans Ombudsman made clear today, numerous, pressing gaps remain in the benefits and services provided to veterans. Unfortunately, the Conservatives still fail to present a plan that will offer the best of care and support to our veterans and their families."

The new benefit would ensure that, after turning 65, the total annual income of a veteran permanently incapacitated in the line of duty will be at least 70 per cent of what he or she received in benefits prior to age 65, O'Toole said.

Monthly payments will be calculated on a case-by-case basis, taking into account what each veteran received prior to age 65 and other sources of income the veteran may have.

Veterans Affairs estimates that the "immediate cash cost" will be more than $10 million, with only a few hundred veterans being over age 65 within the next five years.

The program could grow to over $1 billion "in the future," the department said.

When implemented, veterans who are already over age 65 will immediately qualify to receive the benefit.

In the event of the veteran's death, his or her spouse would continue to receive the benefit, O'Toole said. By 2020, the department estimates that some 5,800 veterans and survivors will qualify for the benefit upon turning 65.

Moderate-to-severe service-related injuries can permanently affect a veteran's ability to work after they leave the Canadian Forces and to save for retirement, O'Toole noted.

The new benefit will help "provide lifelong financial security" to these veterans, he said.

"This represents much-needed peace of mind for our veterans and their families as they recover and as they grow older," O'Toole said.

Veterans Ombudsman Guy Parent, who had identified a drop-off in support for veterans after age 65 in his October 2013 report to Parliament, said he "appreciates" Monday's announcement.

"It is nice to see that some of the gaps that are in the new Veterans Charter are being addressed," Parent said.

Under the current system, veterans who suffer career-ending, service-related injuries or illness qualify for a series of benefits including the Earnings Loss Benefit, the Permanent Impairment Allowance, and Permanent Impairment Allowance Supplement.

The Earnings Loss Benefit stops at age 65, which can knock up to two-thirds off a veteran's income.

In addition to the new benefit, O'Toole also announced his department's intention to streamline all benefits and payments to severely injured veterans into a single pension.