Hopes of India's opposition Congress Party forming a government have been set back after socialist leader Mulayam Singh Yadav decided not to support it in a vote of confidence.

The chances of Congress being able to form a government without the backing of the 20 Members of Parliament of Mr Yadav's Samajwadi party, are slim.

Mr Yadav has been in politics for over three decades. He began his career as a member of the Uttar Pradesh state legislature. UP is India's most densely populated state with a population of more than 120 million and over 80 seats in the Indian parliament.

In his early career, Mr Yadav championed the cause of the lower castes and minorities and they still provide him with bedrock support.

Throughout his career, he has been able to exploit a growing perception among many voters in UP that the Congress Party was represented only by high caste Brahmins or the elite.

His consistent anti-Congress stance paid off in last year's general election when the Samajwadi party sent the second highest number of MPs, after the BJP, from UP to the Indian parliament.

Minorities man

Although much of Mr Yadav's career has been spent fighting regional issues, he has become prominent in central politics. He took a strong strong stand against the demolition in 1993 of a mosque in Ayodhya by Hindu hardliners.

This further enhanced his reputation as a key supporter of the minorities. It also added to his secular credentials at a time when many in UP were concerned about the uneasy mix of religion and politics.

Mr Yadav has recently attempted to broaden his support base in UP, and appointed Amar Singh, a politician from the wealthy Thakur caste, with this objective in mind.

Possible coalition leader?

In 1994, Mr Yadav allied himself with the Bahujan Samaj Party (BSP), a regional party led by backward caste leaders Kanshi Ram and Mayawati.

However this alliance ended after a bitter row over the distribution of votes. The BSP which has close links with Congress is now a threat to his power base in UP and this could be among the reasons for Mr Yadav's announcment that he is not prepared to support a Congress minority administration.

Mr Yadav's first break in central politics came in the summer of 1996, when the Congress Party lost the elections to a United Front coalition led by HD Dewe Gowda. He was appointed defence minister.

Some commentators say that Mr Yadav wants his share in central politics once again and that this may be another reason why he was unwilling to support Congress without his party having any ministerial representation.

However, given the turbulent nature of Indian politics, the possibility of Mr Yadav forming a coalition government which includes Congress cannot be ruled out.