Biden to speak Thursday about Afghanistan amid swift US pullout

President Joe Biden on Thursday will offer his most extensive comments to date about the US withdrawal from Afghanistan, a pullout that is raising concerns about a civil war there and drawing Republican criticism.

A White House official said Biden would update the American people on the situation and that no major policy pronouncements were expected.

The Democratic president, who is due to speak at 1:45 pm (1745 GMT), has been under pressure from critics to give a more expansive explanation for his decision to withdraw.

The United States last weekend abandoned Bagram air base, the longtime staging ground for US military operations in the country, effectively ending America's longest war. The Pentagon says the withdrawal of US forces is 90% complete.

Read: US pullout from Afghanistan over 90% complete: Pentagon

Washington agreed to withdraw in a deal negotiated last year under Biden's Republican predecessor, Donald Trump. Biden overruled military leaders who wanted to keep a larger presence to assist Afghan security forces and prevent Afghanistan from becoming a staging ground for extremist groups.

Biden's order in April to pull out US forces by Sept 11 after 20 years of conflict has coincided with major gains by the militant Taliban movement against overwhelmed Afghan forces after peace talks sputtered.

The commander of US troops in Afghanistan, General Austin Miller, warned last week that the country may be headed toward a civil war.

The US intelligence community believes the Afghan military is weak and that the Kabul government's prospects for survival in the short term are not good, US government sources familiar with official assessments said.

White House spokesperson Jen Psaki said Biden would meet his national security team on Thursday "to receive a periodic update on the progress of our military drawdown from Afghanistan."

Read more: Pentagon defends secretive exit from Afghan airbase

"Early tomorrow afternoon, the president will make comments on our continued drawdown efforts and ongoing security and humanitarian assistance to the ANDSF and the Afghan people.”

ANDSF is the acronym for the Afghan National Defense and Security Forces.

Some Republicans are criticising Biden for the pullout, although Trump had also sought to end American involvement in the war.

Biden met Afghan leaders on June 25 and said US support for Afghanistan would be sustained despite the pullout.

"Afghans are going to have to decide their future, what they want," Biden said at the time.

The United States plans to leave 650 troops in Afghanistan to provide security for the US Embassy.