With no formula acceptable to both parties emerging out of discussions between Congress political secretary Ahmed Patel and NCP general secretary Praful Patel, a meeting between NCP chief Sharad Pawar and Defence Minister Pranab Mukherjee slated for this evening was called off at the last hour.The meeting may take place tomorrow. For the record, Congress general secretary Margaret Alva told reporters that Pawar, who was busy during the day in an ICAR conference, was feeling ‘‘very exhausted’’.Sources, however, said Pawar has used exhaustion as a ploy to build pressure on the Congress. By tantalising the Congress with chief ministership, he has already deprived it of the pleasure it could derive from victory. The effect of delay in government formation was in full evidence today as Sushilkumar Shinde left the Capital for Mumbai to hand in his resignation to the Governor. According to sources, the Congress has refused to entertain the NCP proposal to either concede the chief ministership to the latter or form a government with outside support from the NCP. The latest proposal on the table is to rotate the post between the two allies mid-way through the five-year term.The Congress had sought time to study the NCP proposal. According to sources, senior Congress leaders are not in favour of the outside-support idea as they feel it would project the image of an unstable government.