Afghanistan President Ashraf Ghani on Wednesday said he spoke with his U.S. counterpart Joe Biden on telephone regarding Washington's plan to withdraw all American troops from the Middle Eastern country by September 11.

Bide is expected to announce the troops pullout within hours, ending 20 years of military involvement in Afghanistan.

"I had a call with President Biden in which we discussed the U.S. decision to withdraw its forces from Afghanistan by early September. The Islamic Republic of Afghanistan respects the U.S. decision and we will work with our U.S. partners to ensure a smooth transition," Ghani said on Twitter.

"Afghanistan's proud security and defense forces are fully capable of defending its people and country, which they have been doing all along, and for which the Afghan nation will forever remain grateful."

Roughly 2,500 American troops are still on the ground in Afghanistan, where they advise and assist Afghan security forces. There are an additional 7,000 NATO troops who have been training Afghan soldiers. 

The war in Afghanistan began in October 2001 and was prompted by the September 11 terrorist attacks on the U.S., which left 3,000 people dead.

At the time, the Taliban was sheltering 9/11 mastermind Osama Bin Laden and his Al-Qaida network. The joint deployment of U.S. and NATO forces marked the first and only time the alliance invoked Article 5, which states that an armed attack against one or more allies in Europe or North America is considered an attack against all.

The Biden administration's September deadline comes five months after the May 1 withdrawal former U.S. President Donald Trump had agreed with the Taliban last year.