The former UP chief minister alleged that BJP was trying to use communal tension for political gains in the upcoming bypolls and objected to RSS members being given "constitutional" posts.
She also condemned the heckling of chief ministers, saying such "indecent" behaviour by BJP and RSS workers would only weaken the federal structure.
"RSS is emerging as a stronger unconstitutional and unaccountable organisation than before and its head's recent statement on Hindutva can lead to communal tension in the country," Mayawati told reporters here while referring to remarks by RSS chief Mohan Bhagwat.
"Keeping aside all traditions and rules, BJP is putting RSS people on constitutional posts which could lead to problems," she said.
She lashed out at BJP and RSS over recent incidents of chief ministers of some states being booed in the presence of the Prime Minister Narendra Modi.
"Out of narrow mindedness, BJP and RSS workers have been behaving in an indecent manner which could further sour relations between the Centre and states and the federal structure would also be weakened", she said.
"It is unfortunate that BJP has been terming such behaviour a result of Modi's popularity and trying to gain political mileage out of it," she said, while terming the Modi government's performance in the last three months as "disappointing".
Mayawati said that it was enough time for a majority government to start fulfilling its promises and bring "achchey din" to live up to the expectations of the people.
"They had made a number of promises on power, unemployment... but till now they have not prepared a roadmap for initiating concrete steps in this direction and the old disappointment is growing among the people," she said.
"It is because of this that even the NDA constituents are now seen asking for more time for the Modi government," she said adding that BJP supporters are feeling discouraged.
On communal unrest, she said such incidents go on to prove that BSP's apprehensions were correct that a BJP government at the Centre would lead to a rise in communal riots which would hamper progress.
She said Modi referring to himself as "pradhan sewak"was not enough."His voice is still that of promises and allurements whereas now he has to show his work".
The former chief minister alleged that Modi and BJP came to power by misguiding people and using money in the Lok Sabha elections as had been done by the Samajwadi Party in the last assembly polls.
She alleged that BJP workers have started behaving like the SP workers by taking law into their hands.
"Instead of protesting on roads, they should exert pressure on their government at the centre to impose President's rule in the state," she said.
Mayawati alleged that there was a tacit understanding between BJP and SP and claimed that the people want her to return to power.
To a question on the newly acquired proximity between the SP leaders and Amar Singh, she said, "I would be happy as you all know that he finishes off the party he joins.... You can see the records".
Asked about BJP state unit including issues of conversion of hindus in the agenda for the UP BJP meeting, Mayawati said that it would encourage communalism.
She exuded confidence that despite all out efforts, BJP would not be able to win over dalits as they will never fall prey to its designs.
On reports that the main accused in the Badaun incident have been found to be not guilty, Mayawati said that it was posed a serious question before the people.
"If the main accused are not guilty, who has killed the two girls This should come out", she said without elaborating saying that as the investigation by the CBI was on, it would not be right to say more.
She also condemned Arun Jaitley's comments on rape incident.
The BSP president termed as political rather than diplomatic Modi government's decision to call off foreign secretary level talks between India and Pakistan following the neighbouring country's envoy meeting separatist leaders of Jammu and Kashmir.
"BJP leaders feel that the party can get its benefit in the assembly elections in Jammu and Kashmir," she said adding that her party feels that the talks should not have been scheduled in the first place keeping in mind continued ceasefire violation by Pakistan on the border.
She said BJP must not forget that "they got only 31 per cent votes in the Lok Sabha elections despite all their drama thereby proving that 69 per cent population of the country is still against their narrow and divisive politics".
Mayawati said that an important meeting of her party would be held here on August 30 and 31 during which strategy for the coming assembly elections in some states would be decided, besides guidelines wil be issued for strengthening the party base.