Gay and lesbian couples will be able to wed in the ACT after a bill to legalise same-sex marriage passed the territory’s Legislative Assembly. People in the public gallery clapped and sang Love Is In The Air when the bill passed shortly before midday today. The first marriages are likely to take place from December. But the federal government has flagged a challenge to the laws in the High Court. Federal Attorney-General George Brandis says his government has legal advice that the ACT’s legislation is invalid because it is inconsistent with the provisions of the Commonwealth Marriage Act. ‘‘Irrespective of anyone’s views on the desirability or otherwise of same-sex marriage, it is clearly in Australia’s interests that there be nationally consistent marriage laws,’’ a spokesman for Senator Brandis said in a statement today. Senator Brandis has asked the ACT government not to put the new laws into effect until the court can determine their validity, but Chief Minister Katy Gallagher has vowed to press ahead. ‘‘I don’t believe this bill in any way challenges, diminishes or undermines the religion or faith of any individual,’’ she said during assembly debate on the bill. ‘‘If we are to be judged by a higher being on this law, then let it be so.’’ Ms Gallagher’s openly gay deputy Andrew Barr broke down in tears during debate on the bill. ‘‘The sacrifice, the suffering, the struggle and the tireless exertions and passionate concern of gay and lesbian Canberrans, their parents and their families finds a voice and finds a champion in this Assembly,’’ said Mr Barr, who is in a civil union with partner Anthony Toms. More than 200 people were present to watch the debate, with the public gallery packed and people who couldn’t squeeze in watching the debate broadcast in another room. Opposition leader Jeremy Hanson told the assembly legalising same-sex marriage was not a responsible course of action. ‘‘We do not see the ACT Assembly as a vehicle to drive national agendas on social agendas,’’ he said. Greens MLA Shane Rattenbury, who has the deciding vote in the 17-member assembly, said it was a landmark moment for the ACT. Federal Labor MP for the Canberra electorate of Fraser, Andrew Leigh, congratulated the ACT on the bill and said the Abbott government’s challenge plan was ‘‘mean-spirited’’. ‘‘What the ACT has done is simply allow two people who love each other to have that love recognised by way of marriage,’’ Dr Leigh said in a statement. ‘‘It isn’t going to weaken heterosexual marriages like mine. This is going to make us stronger as a societ -AAP