When D.C. Mayor Vincent Gray pledged in February to hike pay for District employees, the unions representing police officers and firefighters scoffed.

But when Gray unveiled his budget proposal last week, he included tens of millions of dollars to make paydays a little bigger for city workers.

"The mayor has always said that it's time for us to repay the hard work of D.C. government employees," said Pedro Ribeiro, Gray's spokesman. "I don't know how much more unequivocal we can be."

But even with Gray moving to match his rhetoric with policy, the public safety unions remain doubtful, a stance that stems from years of mired contract negotiations.

"I have absolutely no idea what they're doing," said Kristopher Baumann, chairman of the city's police union. "The mayor's public statements on this have not matched anything they've done at the bargaining table."

And Edward Smith, who leads the firefighters union, questioned whether the proposed dollars would ultimately materialize.

"I'm still skeptical," Smith said. "I haven't seen the effort put forth at negotiations."

The two unions have been locked in contentious talks with the District about new contracts for years after their last deals expired in 2007.

Despite Gray's public push for bigger salaries, Baumann accused Gray of exploiting labor groups for political gain just years after those organizations helped propel Gray into the city's top job.

"This is not a labor-friendly administration. This is an administration that's interested in keeping Vincent Gray in office," Baumann said. "They work with labor when it's to their political advantage."

But other labor unions have welcomed the latest pay proposal from Gray, who last year pushed a plan through the D.C. Council to pay city employees for furlough days they were forced to accept in 2011.

Gray also moved last year to restart the Labor-Management Partnership Council, and records show he has since chaired at least three meetings.

"If you talk to a majority of labor leaders in this city, they will tell you that we've done a great job," Ribeiro said. "We are partners with labor. Things get accomplished when we work in partnership, not in opposition to each other."