Officials in Sana'a confirmed that air raids had targeted Ayad al-Shabwani, one of six fighters the government first claimed to have killed last week. Reports from Marib province tonight said there had been four attacks and quoted tribal sources as confirming Shabwani's death.

Offensive actions against al-Qaida in the Arabian peninsula (Aqap) have intensified under US pressure since the Christmas Day attempt to bomb an airliner over Detroit. Western diplomats say Yemeni authorities are now showing more resolve to combat terrorism. Troop reinforcements have been sent to three provinces where the group is said to be operating.

Anwar al-Awlaqi, the US-Yemeni cleric suspected of links with the alleged Detroit bomber, the Nigerian student Umar Farouk Abdulmutallab, has said meanwhile that he has no intention of surrendering to the government.

Abdulilah Sheaya, a Yemeni journalist and expert on al-Qaida, said Awlaqi had not held any talks with the authorities or tribal intermediaries as had been claimed. "He denied that there are any negotiations and insists he will not surrender," Sheaya told the Guardian.

US officials have accused Awlaqi of having links with Major Nidal Malik Hasan, suspected of shooting dead 13 people at a Texas military base in November. Awlaqi is in hiding.

Aqap and its two senior leaders were added to the UN list of terrorist organisations one day after the US state department took the same step. The move was necessary because Aqap was created least year by a merger of the groups that had previously operated separately in Saudi Arabia and Yemen. It would allow US prosecution of those associated with it, or who provide assistance to it.

Western concerns about Yemen were again underlined today with news of the suspension of Yemenia flights between Sana'a and London pending changes to security arrangements. Tim Torlot, Britain's ambassador to Yemen, described al-Qaida as posing "a severe threat". But there had been excellent co-operation with the Yemeni authorities, he said.

The Yemen situation will be discussed at a conference convened by the UK in London next week. It will examine the country's chronic economic problems and seek ways to improve relations between international donors and the Sana'a government. "The solutions to Yemen's problems go far beyond the security arena," Torlot said. The meeting, set to last for just two hours, would be "short and strategic".

President Barack Obama has insisted he will not send troops to Yemen for fear of provoking a backlash, while the Yemeni government insists it can defeat al-Qaida alone, with US financial help and intelligence support. The administration is considering giving the Pentagon expanded powers to train and equip Yemeni forces including special counter-terrorism units controlled by the interior ministry. "We do not have [military] boots on the ground [in Yemen] and we have no intention … of having boots on the ground," an official told the Washington Post. "But we want to make sure that we have the expertise and capabilities that can work with the Yemenis to provide them with the wherewithal and the capacity that they need."