LJUBLJANA (AFP) - Slovenia will probe claims that the United States tapped its international phone lines between 2005 and 2008, Prime Minister Miro Cerar said on Friday (Oct 2), after local media said Washington had intercepted calls to Brussels, Amsterdam and Rotterdam.

"First we have to determine the facts and once we have them, we will adopt a position," the prime minister told journalists, adding that he has ordered an investigation.

Television channel POP TV said on Thursday it had obtained documents showing the US National Security Agency (NSA) - in an operation code-named Eikonal with the German secret services BND - had tapped all calls from Slovenia to Brussels, Amsterdam and Rotterdam between 2005 and 2008.

Austrian Green party MP Peter Pilz told POP TV that the NSA was trying to find out how much information it could actually extract from massive phone tapping, adding that his country as well as Holland and Germany had been affected.

Slovenia, a former Yugoslav country that declared independence in 1991, joined the European Union and NATO in 2004.

In EU powerhouse Germany, a probe into the alleged tapping of Chancellor Angela Merkel's mobile phone was dropped due to lack of proof.

In July however new claims emerged that Washington had spied on Foreign Minister Frank-Walter Steinmeier.