Sydney - Australian Prime Minister Kevin Rudd was Friday chastised for "conduct unbecoming" over the salute he gave US President George W Bush during a social gathering for world leaders in Bucharest, Romania.

Film of the odd gesture at the NATO meeting was shown repeatedly on local television. Opposition Liberal Party leader Brendan Nelson described Rudd's behaviour as "conduct unbecoming of an Australian prime minister" while Greens leader Bob Brown said the salute carried a "subservient connotation."

"It takes seasoned maturity to ensure Australia is never second-rated in the international arena and Mr Rudd is not there yet," Brown said. "We are not the 51st state of the US and Mr Rudd's salute carried a subservient connotation many Australians won't like."

Rudd, who is midway through a 17-day world tour, laughed off the controversy. "It was just a joke," he told reporters travelling with him. "I was just saying 'hi' to the president of the United States. I was with him the other day. I went over and had a chat actually." (dpa)