Mukherjee cancelled his scheduled trip to Kolkata to take part in the negotiations to persuade Ramdev from going ahead with his indefinite fast, official sources said.
Law Minister Veerappa Moily, who was to fly to Mangalore, also scrapped his plans apparently for the same reason, they said.
Hectic back-channel efforts were on to placate Ramdev, who has raised issues of black money and corruption, as the government is keen to avert an Anna Hazare-like protest on the streets.
Close aides of Ramdev said even if the government concedes to all the demands, the ''satyagraha'' will take place for three days at least.
Meanwhile, a large number of supporters of Ramdev started pouring into Ramlila Maidan here from across the country carrying flags and festoons to join the yoga guru's proposed fast against corruption.