Senator Lindsey Graham wrote: “This despicable terrorist attack against innocent civilians at the Kabul airport, which injured American Marines, is a reminder of the depravity the world faces from Afghanistan.”
While there are no reports from the British military of government casualties, US soldiers have been hurt, a UK official said.
"We are working urgently to establish what has happened and its impact on the ongoing evacuation effort.
"Our primary concern remains the safety of our personnel, British citizens and the citizens of Afghanistan.
"We are in close contact with our US and other NATO allies at an operational level on the immediate response to this incident,” a UK government spokesperson said.
The attacks that killed at least 12 US service members left Biden with increasingly fraught choices: continue the evacuation and risk more deaths or end it earlier than planned and risk leaving behind Americans who are still seeking to leave the country.
As details of the attacks emerged, the White House rescheduled Biden's first in-person meeting with Israel's new prime minister.
A video conference with governors about Afghan refugees arriving in the United States was also canceled.
Biden had pledged to get out of Afghanistan every American who wished to leave.
As of Wednesday, the State Department said about 4,500 American citizens had been flown out, with about 1,500 yet to go.
Kabul airport explosions believed to have been caused by suicide bomb terror attack