New Delhi (PTI): The UPA on Saturday struggled hard to conjure up 271 for government survival in Tuesday's trust vote as the Congress put up a brave front ruling out Prime Minister Manmohan Singh's resignation, claiming he will sail through comfortably.

Seeking to scotch speculation that Singh may have to step down before the July 22 vote of confidence in the Lok Sabha if the UPA fell short of a simple majority, Congress spokesman M Veerappa Moily, said "the question does not arise as he will win the trust vote comfortably".

But several UPA leaders conceded in private that it will be a "close call". Besides not knowing which way certain small groups and independents will vote, the UPA is also worried about ensuring that its flock stays together and there is no cross voting.

As suspense mounted in the run-up to voting, Congress chief Sonia Gandhi, met party MPs at her 10, Janpath residence, and asked them to put up a united face to ensure the government's victory in the trial of strength.

Congress Haryana MP Arvind Sharma, who attacked the party and praised Mayawati, giving enough hints that he will be moving towards the BSP, did not turn up for the meeting. Kuldeep Bishnoi, another rebel Congress MP, was also conspicuous by his absence.

But Atma Singh Gill, a dalit MP who was being wooed by the BSP, came out in open support of Gandhi and the government.