The Islamic State group released a video purportedly showing the burning alive of a Jordanian pilot.
US President Barack Obama offered condolences to the people of Jordan and King Abdullah II for the killing of a Jordanian pilot by Islamic State militants and declared that the US and its allies are determined to see the militants and their "hateful ideology banished to the recesses of history."
US Vice President Joe Biden, who lunched with the King in Washington on Tuesday, also condemned the killings and called for the release of all prisoners held by Islamic State.
The reactions from the President and the Vice President came after the Jordanian military confirmed the death of Lt. Muath Al-Kaseasbeh, 26, who fell into the hands of the militants in December when his Jordanian F-16 crashed in Syria. He is the only pilot from the US-led coalition to have been captured to date.
A video released online on Tuesday purportedly showed Al-Kaseasbeh being burned to death by his captors following a weeklong drama over a possible prisoner exchange.
"Lieutenant Al-Kaseasbeh's dedication, courage, and service to his country and family represent universal human values that stand in opposition to the cowardice and depravity of ISIL, which has been so broadly rejected around the globe," Mr Obama said.
Earlier, Mr Obama had said that if the video was authentic it was yet further evidence of the Islamic State group's "viciousness and barbarity."
He said the death would "redouble the vigilance and determination on the part of our global coalition to make sure they are degraded and ultimately defeated."
King Abdullah II of Jordan, who was in Washington for meetings with Mr Biden and Secretary of State John Kerry, was to attend Thursday's National Prayer Breakfast, which Mr Obama is also scheduled to attend. While there were no plans for Mr Obama to hold a formal session with the king, White House spokesman Josh Earnest said there was a chance they could see each other at the prayer event.
King Abdullah met privately on Tuesday with members of the Senate Foreign Relations Committee. The panel's Republican chairman, Senator Bob Corker offered condolences at the start of the meeting. King Abdullah had no comments to reporters who shouted questions as he arrived for the meeting.