Washington: Any hasty withdrawal of American troops from Afghanistan, as in the case of Syria, would pave way for another 9/11, top US lawmakers and experts have warned.

President Donald Trump on Wednesday decided to pullout a significant number of American troops from Afghanistan, a day after he announced a withdrawal from Syria.

Currently, the US has nearly 15,000 troops in Afghanistan working either with a NATO mission to support Afghan forces or in separate counter-terrorism operations.

Trump is considering pulling out some 3,000 troops from the war-torn country.

The senators termed the withdrawal of American troops a high risk strategy.

"The conditions in Afghanistan --at the present moment-- make American troop withdrawals a high-risk strategy. If we continue on our present course, we are setting in motion the loss of all our gains and paving the way toward a second 9/11," Senator Lindsey Graham said.

The Republican Senator from South Carolina, who has just returned from Afghanistan, said that Islamic State of Iraq and the Sham-Khorasan (ISIS-K), an Afghanistan-based affiliate of ISIS, remains a direct threat to the US and they would dramatically benefit from a reduced American troop presence.

"Our Afghan partners are incapable of subduing the threat posed by ISIS-K alone. In addition, our intelligence capability and military might cannot be replaced by any other regional ally when it comes to subduing ISIS-K in Afghanistan or Pakistan. Like in Syria, troop withdrawal should be based on conditions on the ground," Graham said.

The withdrawal of the American troops from Afghanistan could take place in the next several weeks, according to media reports.

The lawmakers suggested that US' ongoing efforts in Afghanistan is a must to prevent another 9/11 type of terror attack.

"Our ongoing efforts in Afghanistan are necessary to ensure another 9/11 does not occur. With threats rising from ISIS-K and other terrorist groups, America's presence in Afghanistan today is as important as it has ever been to protect the homeland and our allies," Congressman Jim Banks said.

He said that it was important to prevent the terrorists from regaining control in Afghanistan.

"While we all want an end to the America's longest running war, it must be done the right way. Withdrawing half our troops from Afghanistan at this critical time is a major risk that would lead to greater instability and jeopardise America's national security," Banks said.

Congressman Will Hurd said:"An American retreat from Syria emboldens ISIS. An American retreat from Afghanistan emboldens Al-Qaeda and undermines the ultimate sacrifice already paid by thousands of Americans. Both will threaten our Homeland again".

Husain Haqqani, the former Pak Ambassador to the USA, indicated that the withdrawal of troops would be an immense boost for terror outfits such as the Taliban.

"If stories about US drawdown from Afghanistan are true, President Trump will have done exactly what President Obama did: Send troops in, only to withdraw them prematurely, thereby proving the Taliban's maxim: Americans have watches, we have time," he said.