SHILLONG, February 27: A five-member coalition ministry under Congress Legislature Party leader S C Marak was sworn in by Meghalaya Governor M M Jacob at Raj Bhawan here this afternoon.Jacob administered the oath of office and secrecy to Chief Minister S C Marak, Deputy Chief Minister D D Lapang and three Cabinet ministers - Kitdor Syiem, J D Rymbai and Lotsing Singh Sangma - an hour behind schedule.United Democratic Party leader B B Lyngdoh had paraded 32 legislators before him at Raj Bhawan just one hour prior to the scheduled swearing-in ceremony of the Congress coalition government.The Governor last night had invited CLP leader S C Marak to form the government. The Congress with 25 legislators in a 60-member Assembly had staked a claim with the support of the HSPDP and Independents with three legislators each.The UDP with 20 members had also staked its claim assuring the support of BJP, HSPDP and PDM with three MLAs each besides two Independents and a lone GNC legislator. In view of thesedevelopments, Jacob asked both parties to furnish a written communication of support from the legislators. In the event, it turned out that only the BJP had furnished unconditional support to the UDP in writing.However, Governor Jacob seemed to have changed his mind as late as Thursday night, inviting the Congress - the single largest party with 25 legislators - for the swearing-in ceremony scheduled for Friday and asking it to prove majority in the Assembly by March 12. But UDP leader B B Lyngdoh's surprise move - producing 32 legislators along with a written letter of support - led to speculation about whether a Congress-led coalition would actually be sworn in, even as Jacob and UDP leaders along with the supporting legislators went into a huddle in one room at Raj Bhawan.However, the meeting over, Jacob stuck to his original plan. Having failed to convince the Governor to postpone the swearing-in ceremony, UDP leaders next asked him to reduce the period before the trial of strength from 14 daysto 48 hours.But it was a despondent Lyngdoh who emerged from the meeting, accompanied by HSPDP legislator and president H S Lyngdoh - who till late Thursday afternoon was flirting with the Congress - and others. Speaking to mediapersons, Lyngdoh said the swearing-in of a Congress-led minority coalition government was highly ``unconstitutional and illegal''.Rushing to the Assembly for a strategy meeting, he said he would take the issue to the people. In the same vein, BJP general secretary P B Archarya who is in charge of the north-eastern border states said: ``It is a conspiracy and he (the Governor) is playing into the hands of a political party''. Jacob for his part justified his decision to invite the Congress, saying former President S D Sharma too had invited the single largest party, the BJP, to form the government at the Centre. He was merely going by convention, he added. Citing the decision taken at the Governors' Conference, he said it had been resolved that a Governor would first invitepolitical parties with pre-electoral alliances to form the government and, in their absence, the single largest party. He brushed aside fears that the 14-day period would encourage horse-trading.Meanwhile, the UDP, with its allies, has formed a United Parliamentary Forum. The Forum will move the Guwahati High Court to challenge what it calls the ``illegalities of calling the Congress with only 25 legislators to form government'' by Jacob. While admitting that he was heading a minority Congress-led coalition government with only 28 legislators, Chief Minister Marak said he was confident that the HSPDP will come back to them.