Sir Elton formalised his relationship with David Furnish in 2005

The musician, on an Australian tour, was asked if he had a message for Howard, whose government overruled a local law allowing gay unions in June.

"Up yours!" replied the outspoken star, who "married" his partner David Furnish in a civil ceremony last year.

The issue of gay marriage has been high on the political agenda in Australia in recent months.

The Australian Capital Territory - the area around Canberra - became the first part of the country to legally recognise gay relationships when it voted on the issue in May this year.

But many members of Mr Howard's conservative government opposed the change, and the law was invalidated.

'Not homophobic'

Attorney General Philip Ruddock said that federal law clearly defined marriage as being only between a man and a woman.

Mr Howard denied the move was homophobic, adding that it was a question of preserving marriage as an institution with "special character".

"If you look at the legislation, what it effectively says, a civil union is not a marriage, but it will be treated for all purposes as being equivalent to a marriage," he said.

Sir Elton has long been an advocate of gay rights, and caused an outcry earlier this month when he called for organised religion to be banned, and accused it of trying to "turn hatred towards gay people".

Organised religion lacked compassion and turned people into "hateful lemmings", he told the Observer Music Monthly magazine.

But the musician said he loved the idea of the teachings of Jesus Christ and said there were many gays he knew who loved their religion.

He added he would continue to fight for gay rights, "whether I do it silently behind the scenes or so vocally that I get locked up".

Sir Elton and Mr Furnish formalised their relationship in a civil partnership in December last year.

They were granted new rights in areas such as employment, pension and inheritance, but such partnerships are not officially regarded as marriages under UK law.