KOLKATA: Trinamool Congress today dealt a severe blow to the UPA by deciding to withdraw its ministers from the Union government and its support but left open the doors for a possible rapprochement in the next three days.The second biggest constituent of the UPA with 19 members in Lok Sabha sprang a surprise after a meeting of its MPs and top leaders with a caveat that the party could reconsider its stand if the government rolls back its decisions.She wanted total withdrawal of the decision on FDI, raising the cap on subsidised LPG from six to 12 cylinders and reduction of diesel hike from Rs 5 by Rs 3 or Rs 4 for reconsideration of her decision.At one point Banerjee mentioned 24 cylinders but it was not clear whether she was making a demand for that number. "We are withdrawing our support... Our ministers will go to Delhi, meet the Prime Minister and tender their resignations at 3 PM on Friday," TMC chief and West Bengal Chief Minister Mamata Banerjee announced after a three-hour meeting. If the Trinamool Congress goes ahead with its decision to withdraw support, the UPA will be reduced to 251, 21 short of the majority mark of 272 in the 545-member Lok Sabha. However, with the support of outside allies--Samajwadi Party (22), BSP (21) and some others-- the government is still comfortably placed with the support of over 300 members.Congress, however, was unfazed as it maintained that Trinamool Congress is "still a valuable ally" and said it will discuss with government the issues raised by Banerjee.Sources said Congress President Sonia Gandhi is expected to take up the matter with Prime Minister, amid indications that the cap on LPG cylinders could be raised from six to nine per year.The virtual deadline of three days gives Congress and government some room to work out a compromise, observers felt. For this, the government may have to climb down on its stand of not rolling back its last week's decisions.Significantly, reacting to the development, SP made it clear that it would not be influenced by Trinamool's decision and would take an "independent" view.Trinamool has six ministers in the Manmohan Singh government-- one of Cabinet rank and others Ministers of State. Banerjee ruled out supporting the government from outside saying her decision was "not half-hearted".While announcing her decision, she attacked the Congress, accusing it of indulging in "blackmail" politics and alleged that the FDI decisions were to "suppress the coalgate issue. They wanted to divert attention from coalgate to FDIgate." Contending that "somebody will have to bell the cat, somebody", she said, "I waited for three-four days. We thought the government will review (its decisions). We wanted to stay in the government but we were not allowed to stay."Banerjee said her party would not be responsible if the country was forced to go for a mid-term poll. "This government can stay for three months or six months, I don't know. But they have lost the credibility. And if they cannot maintain friendship with us, then they cannot maintain friendship with anybody," Banerjee said. Widening the attack on Congress, she brought in issues like coal block allocation scam, blackmoney and fertiliser price rise.Accusing the Congress of indulging in "blackmail politics", she said whenever it has trouble with any of its allies, it goes to the other. "When they have trouble with Mamata, they go to Mayawati, if they have trouble with Mayawati, they go to Mulayam, if there is problem with Nitish (Kumar of JD-U), they go to Lalu... This is blackmailing politics," Banerjee said.Referring to the FDI decision, she said there are 50 million people in unorganised retail sector. "Where will these people go? There will be disaster. It has not been sustainable even in the West."While Banerjee was holding meeting with her party leaders, the Prime Minister held confabulations with senior Cabinet colleagues P Chidambaram and Sharad Pawar.Pawar, the leader of NCP, is understood to have assured the Prime Minister that his party is strongly with the government.