WASHINGTON - U.S. officials say FBI Director James Comey requested more resources to pursue his investigation into Russia's election meddling and the possible involvement of Donald Trump's associates. Days later, he was fired by President Trump.

It is unclear whether word of the Comey request, put to Deputy Attorney General Rod Rosenstein, ever made its way to Trump. But the revelation intensifies the pressure on the White House from both political parties to explain the motives behind Comey's stunning ouster.

Democrats quickly accused Trump of using Comey's handling of the Hillary Clinton email investigation as a pretext and called for a special prosecutor into the Russia probe. Republican leaders brushed off the idea as unnecessary.

White House officials say Trump's confidence in Comey had been eroding for months.