Former UN chief weapons inspector Hans Blix has criticized the US for keeping open the possibility of a military action against Iran.

Blix was in Rome on Friday to take part in an international gathering of experts on nuclear proliferation that was held, coincidentally, during US President George W. Bush's three-day stop in the city.

"The military threat may well be counterproductive,'' Blix said in a news conference.

"The rewards are more important, the carrots rather than the sticks,'' the AP quoted the veteran Swedish diplomat as saying.

Blix tried to avert the 2003 US-led invasion of Iraq because no weapons of mass destruction had been found by UN inspectors.

He said the US and Europe should offer incentives including support for Iran joining the World Trade Organization, improved economic relations and guarantees against outside attacks.

MGH/RA