US-based Mirach Capital has rejected accusations of forgery and charged the troubled Indian financial services group Sahara with walking out of a $2bn loan transaction, key to securing bail for the group's jailed chief Subrata Roy.

Mirach has refused to comment on claims that the banker roped in for the deal was Bank of America (BofA), whose denial being party to any such transaction exposed the alleged forgery, the Press Trust of India (PTI) reported.

Unfazed, Florida-based Mirach has offered to buyout Sahara's iconic hotels in the UK and the US, PTI reported.

Mirach CEO Saransh Sharma said in a statement: "...Initially, Mirach Capital Group reached a deal with Sahara to provide a structured loan package, including taking over the debt on the foreign assets from Bank of China, and a sale of the Indian assets.

"Consistently, Mirach has been interested in an outright sale of the assets, however, Sahara would only agree to exclusivity under the loan structure as outlined."

"Upon recognising their inability to make the first interest payment on the loan, and thus in danger of losing their assets at a discounted rate through default, members of the Sahara Group violated the exclusivity agreement and began shopping the assets for a sale."

"We learned of this after representatives of the Sahara Group approached members of Mirach's syndicate.

"Following Mirach's multiple notices to Sahara that they were in breach of contract, Sahara then began to take an adversarial position against Mirach, and began to attempt to discredit and smear Mirach's reputation.

"Any such claims of Sahara being defrauded by Mirach are untrue and are being presented in an effort to unravel the deal and shelter Subrata Roy.

"Proof of Mirach's financial capabilities were previously verified directly with Sahara's lawyers, and a simple meta data test will show no documents have been forged.

"As per submissions made before the [Supreme Court of India] last month, Mirach was to conduct this deal through funds deposited in an account with Bank of America, which was proposed to transfer funds to the accounts of two Sahara entities.

"Upon agreement of Sahara with support from the Supreme Court of India to a sale of the assets, Mirach stands ready to publicly disclose the identity of our investors who have historically earmarked funds for this transaction to which Mirach has had access.

"...In light of the breach of contract, Mirach is no longer considering an offer for the loan structure, however, remains ready, willing and able to facilitate an acquisition of these assets."

Sahara, in a statement, said it had found out that the Bank of America letter, submitted by Mirach to the Supreme Court of India as proof that it had set aside "sufficient funds" for the transaction, was forged.

Sahara said it learned of the alleged forgery from its lawyer in London, who visited the BofA branch in Los Angeles to verify the letter.

Pursued by Reuters, Sahara did not confirm whether deal talks have been called off.

The group, however, said it will initiate civil and criminal legal proceedings against Mirach and its officials in the US and India for "reckless conduct".

On 9 January, India's highest court cleared the way for Sahara to remortgage London's Grosvenor House and two properties in New York – the Plaza and the Dream Downtown hotels.

Sahara needs to deposit an initial $1.6bn (£1.04bn, €1.4bn) to secure bail for Roy, 66, held in the New Delhi's Tihar jail for almost 11 months in a protracted dispute over refunding billions of dollars to Indian investors in outlawed bonds.

Roy has tried to sell the three hotels from his prison's guest house, but failed to strike deals.