NEW DELHI (AFP) - Delhi's firebrand Chief Minister Arvind Kejriwal threatened to quit on Friday after fewer than 50 days in office as leader of the Indian capital, after moves to bring in anti-corruption legislation were blocked.

"I will consider myself fortunate if I have to sacrifice my post and my life to end corruption," Mr Kejriwal told a raucous meeting of the Delhi state assembly.

Mr Kejriwal, leader of the fledgling Aam Aadmi (Common Man) Party, issued his threat on the floor of the house shortly after local legislators effectively shot down his efforts to bring in anti-corruption legislation - the key plank of his manifesto in a December election.

"It seems to be our last session," Mr Kejriwal, who took office on Dec 28, told the assembly in the Indian capital.

His party won 28 seats in Delhi's 70 member assembly and came to power with the help of the Congress party, which governs at national level.

But Congress decided not to back Mr Kejriwal in Friday's vote, claiming the measure was unconstitutional.

Senior leaders of the Aam Aadmi Party were due to gather on the outskirts of the capital later on Friday to decide on their next move.

One of his top lieutenants, Mr Yogendra Yadav, told reporters that the Delhi government's resignation "cannot be ruled out".

Mr Kejriwal, who is a self-described "anarchist", is due to address supporters at the meeting.

While his elevation to one of the most important political posts in India was initially widely welcomed as a much-needed shock to the system, the former tax inspector has since come in for heavy criticism over a series of stand-offs with the authorities.

He staged a sit-in on the pavement close to the national parliament last month, triggering chaos in the city centre, as part of a push to be given greater powers of control over the police.