Washington, Apr 20 (IANS): Two US soldiers were questioned by Mexican troops earlier this month while conducting a surveillance operation on the American side of the border, defence officials told CNN.

"On April 13, at approximately 2 p.m., five to six Mexican military personnel questioned two US Army soldiers who were conducting border support operations in an unmarked (Customs and Border Protection) vehicle near the southwest border in the vicinity of Clint, Texas," the US Northern Command said in a statement on Friday.

"The soldiers were appropriately in US territory" during the encounter.

During the incident, the Mexican soldiers pointed their weapons at the US troops, removing a soldier's sidearm and returning it to the unmarked American vehicle, the defence officials said.

The Mexican troops were armed with what appeared to be assault rifles.

The officials told CNN that the US soldiers allowed the weapon to be taken "in an attempt to de-escalate a potential volatile situation".

One of the American soldiers spoke some Spanish and was able to explain the situation to the Mexican forces. The two sides talked the incident over and promised to de-conflict in the future, the officials said.

President Donald Trump had previously ordered the active duty military to support border security and the US has some 3,000 active duty troops supporting the Department of Homeland Security on the southern border with Mexico in addition to some 2,000 National Guard troops.

The Pentagon expects additional troops to be sent to the border to support additional pending requests for assistance from the Department of Homeland Security.