Security officials in Yemen have foiled a plan by fighters linked to al-Qaeda to bomb an air base used by US soldiers in the southern province of Lahj to train local forces in combating terrorism, officials have said.

A military official disclosing information on condition of anonymity said a car packed with explosives was discovered on Saturday in a wooded area near the gate of al-Anad air base.

He added that it had apparently been "smuggled in several days ago".

"We foiled an attack by a car packed with explosives that managed to breach several security checkpoints leading into the air base.

"The attack was to be implemented today (Saturday)" and "Americans on the base were the target of the attack," he added.

Lahj governor Ahmed Abdallah al-Majidi was quoted on the ministry website "The military police defeated an afternoon attack on the al-Anad base."

"The vehicle belongs to al-Qaeda," Majidi said, adding that its seizure led to the discovery of a "large quantity of explosives, gas cylinders and anti-tank rockets and clothes for female drivers".

He did not explain why the attackers failed to detonate the explosives immediately after the car was smuggled into the base.

Last year, al-Qaeda overran most of southern Yemen's Abyan province seizing its capital Zinjibar and several other towns due to the weakening of the central government control by an Arab Spring-inspired uprising.

After almost nine months of continued protests, Ali Abdullah Saleh quit as president last November as part of a deal initiated by Gulf countries.

On May 12 this year, under orders from Saleh's successor, Abdrabuh Mansur Hadi, the army launched a massive offensive to recapture territory lost to the rebel fighters.

Western diplomats at the time said the US experts were assisting the army in their battle to destroy al-Qaeda in the Arabian Peninsula, considered by Washington to be the deadliest and most active.