Both reached Dr Roy's house around the same time.
Mr Sangma is learnt to have attempted to persuade the UDP president to change his stand on support to the NPP which is part of BJP-led National Democratic Alliance (NDA) at the centre. The NPP had contested the assembly election on its own but its claim to power is being actively supported by the BJP which wants to keep the Congress out.
Long after Mr Sangma left, Himanta Biswa Sarma, the BJP's master strategist for the Northeastern states, was closeted at a meeting with Dr Roy.

UDP's Donkupar Roy has emerged as the 'kingmaker' after Meghalaya elections.
The UDP is, however, learnt to have decided to stick by its announcement, clearing the road for the NPP's Conrad Sangma.
Son of the former Lok Sabha Speaker PA Sangma who founded the National People's Party (NPP), Conrad Sangma's NPP with its 19 members will meet Governor Ganga Prasad at 5 pm to stake claim to form the government.
Since election to one seat was cancelled due to the death of a candidate, the majority mark in the 59-member house is 30 legislators.
The Congress, which is losing Meghalaya, has ruled it for the last 10 years with Mukul Sangma at the helm. The party won 28 seats in the last assembly polls; it's down to 21 this time.

Congress's Mukul Sangma faces a difficult task to stitch enough support for a majority.
Mr Sangma, who submitted his resignation as Chief Minister, later told reports that he had promised to be back with letters of support from like-minded people. "BJP has only 2 MLAs how would they like to form the government? They want to fire from the shoulder of other political parties," Mr Sangma said.
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The BJP has, however, made it clear that it wasn't looking "at a major role" in Meghalaya with only two lawmakers."That will have to be played by the regional political parties... We will encourage them to form a government. They have to take the plunge. Wherever they feel the BJP can facilitate their discussion, help or inspire, we will be there," said Mr Himanta Biswa Sarma had earlier told NDTV.
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