The US has suspended the processing of all immigration requests for Afghan nationals pending a review of security and vetting protocols, the US Citizenship and Immigration Services announced.

In a post on X, the agency said: The protection and safety of our homeland and of the American people remains our singular focus and mission.

The decision comes after two National Guard soldiers were critically injured in a shooting near the White House. The alleged gunman was an Afghan national who entered the US in September 2021.

US President Donald Trump said the attack was an act of terror, adding that he would take steps to remove foreigners from any country who does not belong here.

Tens of thousands of Afghans entered the US under special immigration protections following the chaotic US withdrawal from the country in 2021 under former President Joe Biden.

Multiple law enforcement sources earlier identified the alleged gunman to the BBC's US partner CBS as Rahmanullah Lakanwal, a 29-year-old Afghan national who entered the country under the program called Operation Allies Welcome.

Trump stated that the US must now reexamine every single alien who has entered our country from Afghanistan under Biden in light of the shooting.

The latest order comes on top of a US travel ban imposed by Trump on nationals of Afghanistan - and 11 other countries - earlier this year.

Afghan nationals holding Special Immigration Visas, available to those who worked directly with the US military before the Taliban took back control of the country in 2021, were among a few exceptions to the sweeping bans.

Earlier this year, Trump also ended a programme that granted deportation protections for thousands of people from Afghanistan, halting a temporary protected status programme that allowed migrants to obtain work permits if it was deemed unsafe for them to return to their homeland.