Russian Ambassador

"Even now, speaking to you, I am afraid to say anything positive about the American president," Russia's envoy to the U.S. told reporters in Moscow.

Flynn resigned as Trump's national security adviser in February.

Flynn was national security adviser until February.

The newly appointed ambassador spoke before the current U.S. government announced further sanctions on Russian diplomats.

According to sources, Sessions will also dispute the account Comey gave under oath of a conversation between the two men.

The question is no longer whether there are grounds to impeach Trump. Is there the political will?

The House Intelligence Committee chairman has made it clear his allegiances are with Trump, not Congress.

"FIND NOW," he demands, referring to leakers in wake of reports that the FBI has refused a White House request to refute recent stories about Trump team contacts with Russians.

The U.S. has said any attempts to link Washington to the attack is "ludicrous."

Pro-government newspapers say the assassin was sent to disrupt Syria negotiation.

The department said the situation with U.S.-based cleric Fethullah Gulen had no bearing on the assassination.

Fethullah Gulen called Ambassador Karlov's killing a "heinous act of terror".

Around 18 Russian experts will assist the investigation into Ambassador Karlov's shooting.

Andrei Karlov was attending a gallery exhibition.