McCain, who was already in Slovenia in 2002, will visit the country to mark the 25th anniversary of diplomatic ties between Slovenia and the US, Pahor's office announced.

Before travelling to Andraž nad Polzelo for the ceremony remembering the crash of a US bomber at the site during World War II, Pahor and McCain will be joined for talks by Defence Minister Andreja Katič and Andrej Osterman, the chief of the general staff of the Slovenian Armed Forces.

They will also visit the Peter Petrič barracks in Kranj, where they will meet troops leaving for NATO mission in Latvia.

McCain, the chairman of the US Senate Armed Services Committee, was the Republican candidate in the 2008 US presidential election, but was defeated by Barack Obama.