LONDON, march 09 (Reuters) - Somalia's government would welcome U.S. air support for an expected offensive aimed at retaking control of areas from al Qaeda-linked al Shabaab rebels, President Sheikh Sharif Ahmed said on Tuesday.

Speaking on a visit to Britain, Sheikh Sharif added that international aid for reconstruction would be needed to secure any areas gained in the push, expected in coming weeks in a test of attempts to restore stability in the Horn of Africa nation.

The New York Times reported on March 5 U.S. forces could get involved by providing airstrikes and Special forces Operations if the offensive succeeded in dislodging al Qaeda fighters.

Asked to comment, Ahmed said: "If the U.S. government provides us with the air support, it will help the situation."

"If that is true, as written in the New York Times, then we would welcome it," he told a news conference through an interpreter.

It was not immediately clear whether Ahmed was referring to the possibility of air strikes or of supporting aerial surveillance. U.S. forces are believed to have conducted aerial reconnaissance of parts of Somalia for several years.

FOREIGN FIGHTERS "ROAMING"

Asked whether he also saw a role for U.S. ground forces in the push, Ahmed said: "I cannot answer that."

Any direct use of U.S. military power would be sensitive. American troops who were part of a U.N. humanitarian mission to Somalia in 1992 and 1993 were forced to pull out after Somali militia killed several marines in an attack on a U.S. helicopter.

Ahmed's U.N.-backed administration intends to oust the rebels from the capital and possibly other areas of the country, which has had no effective central government for 19 years.

His government has struggled to establish its influence, something that has been whittled down by a three-year-old revolt against his administration, which only controls parts of the capital.

Asked how he planned to hold any areas gained in the offensive, a critical task to establish authority, he said: "Our strategy is to mobilise the people, to secure the environment, to return the services and to start reconstruction."

"Our forces have prepared well," he said, but added: "We will need international assistance in the form of humanitarian aid and reconstruction after the liberation of these areas."

The offensive did not close off reconciliation efforts, he said, but he described al Shabaab as having a direct tie to al Qaeda and said both groups cooperated with Somalia's pirates.

The government says hundreds of foreign fighters have joined the revolt from countries in south Asia and the Gulf region and Western nations such as the United States and Britain.

Ahmed said it was hard to tell put a number on al Qaeda fighters in Somalia. "But it's also hard to exaggerate the presence of al Qaeda. It can be seen openly by people inside Somalia -- foreign fighters who are roaming," he said.

"The announcements by al Shabaab and al Qaeda make clear their presence in force. Recent events in Yemen are also a clear indication of the presence of al Qaeda in the area".

He denied reports that Somalis in nearby countries were being recruited to join the offensive, explaining there were plenty of Somalis in Somalia who wanted to serve in the army.