WASHINGTON — As calls for an independent prosecutor intensify on both sides of the aisle, President Trump and aides argued Wednesday that the firing of FBI Director James Comey had nothing to do with the agency's ongoing investigation into possible collusion between the Trump campaign and the Russians.

"He wasn't doing a good job," Trump told reporters about Comey after a Wednesday meeting that only sharpened the debate over the Russia investigation, an Oval Office sit-down with Russia Foreign Minister Serge Lavrov. The Comey issue did not affect the "good meeting" with Lavrov, the president said as he say next to former Secretary of State Henry Kissinger.

Earlier in the day, Trump tweeted: "The Democrats have said some of the worst things about James Comey, including the fact that he should be fired, but now they play so sad!"

Democrats, saying Trump is trying to short-circuit the Russia investigation, united in their calls for the appointment of a special prosecutor — and even some Republicans on Wednesday began to broach the idea.

White House Deputy Press Secretary Sarah Sanders, speaking on MSNBC's Morning Joe and other television news programs, said the FBI director's overall record subjected him to dismissal. Sanders cited the recommendations of Justice Department leaders who said Comey had lost his effectiveness as the bureau's leader — in part because of his handling of the Hillary Clinton email investigation.

Comey announced just 11 days before the November presidential election that he was reopening the probe into Clinton's use of a private email server during her time as secretary of State. As Sanders noted in her interview defending the firing, many Democrats blamed for her loss to Trump in the November election.

Stressing the Trump administration has no plans to get involved in FBI business, Sanders said the Russia investigations will "continue whether Jim Comey is there or not."