Why has the Trump administration revoked more than 175,000 US visas?

US President Donald Trump's administration has revoked more than 175,000 visas held by foreign nationals as the United States expands its immigration crackdown, the State Department said Monday.

Most cancellations followed law-enforcement encounters involving alleged criminal activity, as well as visa violations, fraud, calls for violence and national security concerns, according to a department fact sheet.

“The revocations come as a result of the State Department’s continuous vetting operations, which ensure that visa recipients abide by the terms of their visa and do not endanger Americans,” the department said.

Assault, driving under the influence, theft and drug offences were among the most common reasons for revocations.

The department also said a US embassy in North Africa cancelled more than 100 visas belonging to alleged “birth tourist” parents accused of travelling primarily to give birth in the US so their children could obtain citizenship.

Other cases involved foreign nationals accused of celebrating the assassination of conservative activist Charlie Kirk.

“A US visa is a privilege, not a right,” the State Department said.

The latest figure represents a sharp increase from January, when the department said more than 100,000 visas had been revoked.

The Trump administration has also tightened visa screening, including expanded social media vetting.