Singh had lost the election for the Hisar Lok Sabha seat by a narrow margin of 7,000 votes to former chief minister and Haryana Janhit Congress leader Bhajan Lal in May.

Singh had earlier offered to resign as an office-bearer of INLD after his defeat but that was rejected by Chautala.

'Sampat Singh is one of the seniormost politicians in Haryana. We welcome him in Congress and hope that his experience will benefit the party,' said Hooda here Monday.

The INLD, which ruled Haryana from 1999 to 2005, was trounced in the February 2005 assembly polls. It returned with only nine seats in the 90-member assembly. Chautala, who contested from two seats, lost in the Narwana constituency.