Madrid - Spain stepped up diplomatic activity Thursday in a push to be invited to an economic summit set to take place in Washington in mid-November.

The government was making efforts "in all directions, with everyone, and at all levels," according to government sources.

The United States has invited only members of the G-20 group, of which Spain is not a part, to the meeting.

Prime Minister Jose Luis Rodriguez Zapatero decided on short notice to attend the Asia-Europe meeting (ASEM) in Beijing this week, where he will seek support from G-20 members such as Germany, China, India and Indonesia, the sources said.

Next week, Zapatero will also meet with Mexican and Brazilian leaders during an Ibero-American summit in El Salvador.

French President Nicolas Sarkozy, British Prime Minister Gordon Brown and European Commission President Jose Manuel Barroso have backed Spain's arguments to attend the meeting in Washington. But the United States has only offered to allow one other European representative to explain the Spanish stance at the summit.

Spain has contacted the US Congress and affiliates of presidential candidates Barack Obama and John McCain, the sources said.

However, Zapatero has not discussed the Washington summit with President George W Bush, with whom he has had cool relations since recalling Spanish troops from Iraq after his election victory in 2004.

The Spanish government does not believe that Bush decided personally not to invite Spain to Washington, the sources said. The guest list was simply based on the composition of the G-20, they added.

The G-20 includes Russia and the seven most industrialized countries: the United States, France, Britain, Germany, Italy, Canada and Japan.

The group also includes large developing economies such as Argentina, Australia, Brazil, South Korea, China, India, Indonesia, Mexico, Saudi Arabia, South Africa and Turkey.

Spain should participate in decisions concerning the future of the global economy, because its economy is the eighth-strongest in the world, Zapatero argues.

Organizations such as the International Monetary Fund (IMF) and the World Bank, however, only rank Spain as the 12th-biggest in terms of purchasing power.

Spain had perhaps the "most solid" banking sector in the world, Zapatero boasted recently, after banking giant Santander snapped up British banks hit by the financial crisis.

Spanish per capita income had surpassed Italy, and might overtake France within four years, the premier said.

Spain has long sought a foothold among the most powerful nations of the world.

The opposition People's Party (PP) accused Zapatero of having damaged Spain's chances to attend the Washington summit with his foreign policy, which has focused on relations with Europe rather than with the United States. (dpa)