As the countdown to the UPA government's trust vote begins, two Left parties -- RSP and Forward Bloc � on Friday issued whips to their respective MPs asking them to vote against the Congress-led coalition during the confidence motion on July 22.

In separate whips issued, the parties asked their MPs to be present in the Lok Sabha during the two-day special session beginning Monday and vote against the government.

The RSP and Forward Block have three MPs each. Both the parties have asked their MPs to reach the capital by tomorrow.

"We have asked the MPs to be present in the Lok Sabha during the special session on July 21 and 22 and vote against the confidence motion," RSP general secretary T J Chandrachoodan said.

Three RSP MPs -- Ranen Barman, Joachim Baxla and Sanat Kumar Mandal all from West Bengal-- are expected to reach the national capital soon, sources said.

The CPI(M) and CPI have already asked their Lok Sabha members to oppose the trust vote on July 22.