American air forces situated in Europe planned to have longer training in Bulgaria and Romania, US air forces in Europe commander Tom Hobbins said.

Western Europe's air space was getting smaller because of the more intense civil traffic there, Hobbins said.

The main goals of the US air forces in Europe in 2007 will be increasing effectiveness and strengthening relations with Eastern Europe and Africa.

US interest towards Africa resulted from the continent's natural resources. US officials were also worried that the poverty in Africa could turn the continent into a breeding ground for terrorists, mediapool.bg said.

US secretary of state Condoleezza Rice and Bulgarian Foreign Minister Ivailo Kalfin signed an agreement for military and defence co-operation on April 28 2006.

Following the agreement US will use four Bulgarian military bases for the training of its troops.