US Secretary of State Rex Tillerson on Tuesday met with Russian Foreign Minister Sergei Lavrov for talks on Syria and Ukraine, amid a political firestorm that has placed Moscow's alleged meddling in last year's election back in the spotlight.

President Donald Trump on Monday fired FBI chief James Comey, who was leading a wide-ranging probe into whether Trump aides colluded with Russian officials to sway last year's election, which saw the Republican billionaire defeat Democrat Hillary Clinton.

"I want to welcome the foreign minister to the State Department and express my appreciation for him making the trip to Washington so that we could continue our dialogue and our exchanges that began in Moscow," Tillerson told reporters.

After talks with Tillerson, Lavrov will head to the White House to meet Trump -- an unusual Oval Office welcome for a foreign minister.