Hazare, who rattled the government in April through his fast for a stronger Lokpal that generated widespread nationwide support, said all those fighting against corruption should not be satisfied with the oral assurances of the government.
Hazare said he would join Ramdev at Ramlila Maidan in Delhi, where he is to sit on a fast-unto-death protest, on Sunday, emphasising that there was no divide in the civil society on the issue of corruption.
"I will support Ramdev so that the government does not do what it did when we were fighting. We will fight together against corruption," he said.
Hazare criticised Wednesday's extraordinary step by the government to send four senior ministers, including Finance Minister Pranab Mukherjee, to Delhi airport to receive Ramdev and talk to him there.
"There was no need for so many ministers to go. One or two ministers would have been enough for the talks. When so many ministers go, it means there is a plan of fraud. Sign papers, make promises, all this is to pass time," he said.
"Once the time passes, they (government) will do what they want to. When I went on fast, it reached such a stage that the government conceded to all our demands to save itself. Now, they have backed out," Hazare said.
He was referring to the question of bringing Prime Minister under the purview of Lokpal, which he claimed the government had agreed to earlier but now disfavours.
Claiming that the government has "cheated" activists on the issue of Lokpal and people have realised the "betrayal" by the government, Hazare said, "it is a fraud if the government agrees on certan issues and say the Prime Minister will be accountable under Lokpal and later backs out."
Hazare also noted that the yoga guru has a standing in the public and wherever he goes people gather to hear him.
"Baba Ramdev has been raising the issue of black money from so many days. Why did the government not think of doing something on the issue? People have now come to know what the intentions of the government are," he said.
"Now no more hollow assurances and oral promises. What we want is action and the fight against corruption will continue throughout the country till we get what we want," he said.
He said the government was getting its act together now only after Ramdev made it clear that he would start his agitation from June 4.
"For so many days we are demanding (immediate implementation of the Lokpal Bill), why did the government not listen to us. Now the government is running just because time has to come to sit on fast," he said.
Asked about the bitterness that surfaced recently between government and civil society members of the Lokpal drafting committee, Hazare said he warned that if the draft of the proposed bill was not prepared in time and in line with their demands, they will part ways and hit the streets again.
"Government is not bigger than people. People are bigger than people," he said.
Hazare also made it clear that everybody should come under the ambit of the Lokpal Bill. "All the government officials should come under the ambit of the Lokpal," he said.