Taking a dig at Prime Minister Narendra Modi's frequent foreign tours, he said mere speeches and announcements will not help the public, and demanded that the BJP-led government solve farmers' problems before looking at alliance talks for the forthcoming elections.
Modi had launched the Pradhan Mantri Fasal Bima Yojna in 2015 with the main objective to provide insurance cover and financial support to farmers in the event of failure of any of the notified crops as a result of natural calamities, pests and diseases.
Addressing a rally in Beed district of Maharashtra during his tour of the drought-hit Marathwada region, Thackeray asked how many people received benefits of the government's crop insurance scheme after paying instalments to insurance firms.
"People have got cheques of Rs 2, Rs 5, Rs 50, Rs 100. I don't do 'Mann ki Baat' (referring to Modi's monthly radio programme) but believe in speaking 'jann ki baat'. Allegations are being made that there is a scam of thousands of crores in the crop insurance scheme," he said.
"Who should we question? There is someone called Sainath, who is an expert on the subject, who has written a book. He has said the crop insurance scam is as big a scam as Rafale," Thackeray said.
While the Opposition Congress has been alleging corruption in the Rafale jet deal, the government has denied it.
Claiming that there was a "bubble" of announcements, Thackeray asked the government to "solve the problems of farmers before considering any alliance talks".
The Sena has been regularly hitting out at the BJP despite being part of the government in Maharashtra and at the Centre. Its leaders have often said they would contest the next polls on their own.
Thackeray's party and the BJP had contested the 2014 Lok Sabha polls in alliance but split up at the time of Assembly polls. The Sena joined the state government later.
"Everyday you (Modi) go to different countries and say my country is changing? How many days left (in power) for you now?" Thackeray asked.
"You go to different countries everyday and think our country is changing? Today Russia, tomorrow Japan and day after China. Then say our country is changing. The country may be changing for you but not for people, their conditions, their sorrows are not changing," he said.
The Sena chief said he would not mind if he does not get a single vote after speaking truth, but he was averse to winning elections by speaking lies.
He said the Centre had neither been able to resolve issues or farmers nor constructed the Ram temple.
"If the issue was to be decided by court, why did you make this promise in your poll manifesto?" Thackeray asked.
Hitting out at the Centre's drought assessment team which visited the state last month to take stock of the situation, he said it was "useless" and a mere ploy to show "carrots" to people.
"It needs to be understood who is truly yours and who is not. Mere speeches and announcements do not fill the vessels of people. The central team to assess drought came and went. Did you get anything? It is strange they need a mechanism to see drought even after the area is drought-hit," he said.
Assuring his support to farmers amid the ongoing drought situation, he appealed them to support his party.
The state received inadequate rainfall last monsoon and the government had earlier declared drought in 151 out of the 353 talukas in the state.
Earlier in the day, the Sena leader handed over 100 cattle fodder-laden trucks and other essential supplies to farmers and undertook a tour of the drought-hit region.
Beed, which was earlier a stronghold of the NCP, is now dominated by the BJP while Sena has no presence in the district.