Originally Published: 13 SEP 21 12:13 ET

Updated: 13 SEP 21 12:22 ET

By Nicole Gaouette, CNN

(CNN) -- Secretary of State Antony Blinken is set to testify Monday in what is expected to be a confrontational and emotional hearing about Afghanistan and the chaotic withdrawal that ended America's longest war.

The top US diplomat, the first Biden administration official to publicly account for the events in Afghanistan before Congress, will appear before the House Foreign Affairs Committee and is expected to face a grilling from lawmakers in both parties who have been furious about the outcome. After nearly two decades, more than $2 trillion in US taxpayer funds, the deaths of more than 6,000 Americans and 100,000 Afghans, and a frenzied US airlift effort, Afghanistan has returned to Taliban control.

Along with administration officials, lawmakers were taken by surprise as the Taliban swiftly trounced Afghan troops, leaving US citizens, legal permanent citizens and Afghans who worked with US troops and diplomats struggling to leave the country during the rushed evacuation effort -- or left behind. Many lawmakers were personally drawn in as they scrambled to help constituents escape Kabul.

Blinken, usually steady and unruffled in his public appearances, will encounter angry demands for answers about the true number of US citizens still inside the country, ongoing efforts to help them leave, whether the US plans to formally recognize the Taliban, the fate of US military equipment and why 13 US service members died at Kabul airport in a terrorist attack that the administration knew was coming.

That attack -- claimed by the group ISIS-K -- will also prompt questions about the terrorist threat that Afghanistan poses to the US going forward.

With the Biden administration's announcement Monday that it is providing nearly $64 million in new humanitarian assistance for Afghans to provide food, health care, medical supplies and other relief, lawmakers are also set to ask how the US will keep those funds out of Taliban hands.

Blinken is expected to emphasize ongoing efforts to help US citizens and the citizens of Afghanistan, as well as cooperation with international allies that resulted in the largest airlift in US history, pulling about 124,000 men, women and children out of Kabul in just a few weeks.

Monday's hearing will be the first of two appearances Blinken makes before Congress this week.