Senior Congress leader P Chidambaram on Saturday described electoral bonds as "legalised bribery" and claimed that, as their fresh tranche opens on October 4, it will be a "golden harvest" for the BJP.

The government on Friday approved the issuance of the 28th tranche of electoral bonds that will open for sale for 10 days beginning October 4.

The decision comes ahead of assembly elections in Rajasthan, Madhya Pradesh, Chhattisgarh, Telangana and Mizoram. The poll dates in these states are likely to be announced soon.

In a post on X, Chidambaram noted that the 28th tranche of the electoral bonds will open on October 4 and said, "It will be a golden harvest for the BJP. Going by the past records, 90 per cent of the so-called anonymous donations will go to the BJP."

"The crony capitalists will open their cheque books to write out their 'tribute' to the lord and master in Delhi," the former Union minister said.

Electoral bonds are "legalised bribery", Chidambaram added.

Electoral bonds have been pitched as an alternative to cash donations made to political parties as part of efforts to bring transparency to political funding.

The sale of the first batch of electoral bonds took place in March 2018. The State Bank of India (SBI) is the only bank authorised to issue electoral bonds.

Electoral bonds can be purchased by Indian citizens or entities incorporated or established in the country.

Registered political parties that have secured not less than 1 per cent of the votes polled in the last Lok Sabha or legislative assembly elections are eligible to receive funding through electoral bonds.

The Congress had alleged on Tuesday that the electoral bonds scheme is one of the most "diabolical acts" of the Narendra Modi government as it undermines the electoral system and democracy in the country.