SANAA (AFP) – Security has been ratcheted up around the airport and foreign embassies in Sanaa, Yemeni officials said on Monday, amid fears of strikes by an Al-Qaeda branch linked to a botched attack on a US airliner.

The measures come as US authorities announced intensifying airport security checks on passengers traveling from or via 14 “terror linked” countries, including Yemen.

The US and British embassies in Sanaa remained shut on Monday after closing their doors a day earlier for what they said were security reasons, officials said.

Yemeni officials, asking not to be named, told AFP security had been tightened outside the American and British missions as well as around other foreign missions in the capital.

The US embassy on Sunday said it was closing its doors in response to “ongoing threats by Al-Qaeda in the Arabian Peninsula (AQAP) to attack American interests in Yemen.”

Britain followed suit, with a spokeswoman for the Foreign Office in London confirming its Sanaa embassy had been closed “for security reasons.”

US President Barack Obama has accused the Yemen-based AQAP of arming and training a Nigerian accused of trying to blow up a Detroit-bound Northwest Airlines jet on Christmas Day. Related article: Obama accuses Al-Qaeda

AQAP claimed responsibility for the failed attack and called for strikes on embassies in Yemen.

A Yemeni security official told AFP that police measures “were intensified” on the road to the airport “following the closure of the US embassy.”

“These measures are preventive in case of any attacks by Al-Qaeda in the country, mainly as the road to Sanaa airport is vital,” he told AFP requesting anonymity.

Security had already been tight around the US embassy, which was the target of a car bomb in September 2008 that killed 19 people outside the complex.

Obama’s counter-terrorism advisor John Brennan warned on Sunday of possible attacks by Al-Qaeda in Yemen.

“There are indications that Al-Qaeda is planning to carry out an attack against (a) target inside of Sanaa, possibly our embassy,” he said.

Washington’s Transport Security Administration (TSA) said on Sunday that all passengers flying into the United States from abroad will be subject to random screening or so-called “threat-based” screens.

It further mandated that “every individual flying into the US from anywhere in the world traveling from or through nations that are state sponsors of terrorism or other countries of interest will be required to go through enhanced screening.” Related article: Tougher checks on US-bound flights

Among the affected countries are Yemen, Cuba, Iran, Sudan, Syria, Afghanistan, Libya, Nigeria, Pakistan and Somalia.

Fears of an attack in Yemen grew after AQAP urged Muslims to attack Western targets in the impoverished Arabian Peninsula country after claiming the thwarted airline attack.

“We call upon every Muslim who cares about his religion and doctrine to assist in expelling the apostasies from the Arabian Peninsula, by killing every crusader who works at their embassies or other places (and) declare an all-out war against every crusader on (the Prophet) Mohammed’s peninsula on land, air and sea,” it said in a statement.

London and Washington, meanwhile, have agreed to fund Yemen’s special Counter-Terrorism Unit — a special force which has received US training and assistance.

Brennan described the move as a “determined and concerted effort” but stressed Washington would not open up a new front in Yemen by sending in troops to help the authorities battle Islamist militants.

The government of Yemen, the ancestral homeland of Al-Qaeda chief Osama bin Laden, has welcomed US and British help to fight Al-Qaeda.