Passengers flying into the United States from 14 countries, including Afghanistan, Nigeria and Yemen, will be subjected to enhanced screening techniques, the U.S. Transportation Security Administration said Sunday.

Starting Monday, all travellers on U.S.-bound overseas flights will be subject to random screening, TSA said. Airports are also directed to increase "threat-based" screening of passengers who may be acting in a suspicious manner.

"TSA is mandating that every individual flying into the U.S. from anywhere in the world travelling from or through nations that are state sponsors of terrorism or other countries of interest will be required to go through enhanced screening," the TSA said in a release.

Those techniques include full-body pat-downs, carry-on bag searches, full-body scanning and explosive detection technology, TSA said.

The State Department lists Cuba, Iran, Sudan and Syria as state sponsors of terrorism. The other countries whose passengers will face enhanced screening include Afghanistan, Algeria, Iraq, Lebanon, Libya, Nigeria, Pakistan, Saudi Arabia, Somalia and Yemen.

Umar Farouk Abdulmutallab, the Nigerian man who allegedly tried to set off an explosive device aboard a Northwest airliner on Christmas Day, told U.S. investigators that he received training and instructions from al-Qaeda operatives in Yemen.

The TSA said the ability to enforce the new security measures is the "result of extraordinary co-operation from our global aviation partners."

With files from The Associated Press