Finance Minister Arun Jaitley on Tuesday issued an ultimatum to domestic black money holders to pay their taxes by September 30. He also assured defaulters who declare their income within the stipulated period of immunity from any scrutiny, inquiry, or any prosecution proceedings under the Income Tax Act or the Wealth Tax Act, The Times of India reported.

"People who have undisclosed income and have stayed outside the income tax net, this is the last chance to declare them and sleep peacefully. No one will ask for the source of the disclosed income," Jaitley said, adding that the four-month compliance window, which opened on June 1 and ends on September 30, will not be extended.

According to the Income Declaration Scheme, domestic black money holders can declare their undisclosed income, pay 45% tax and penalty, and escape prosecution. "This is not an immunity scheme. An immunity scheme is one where there is no penalty. In IDS, there is penalty," the Union minister clarified.

On Sunday, Prime Minister Narendra Modi warned defaulters to take advantage of the scheme or face action. "It will be better that you take advantage of the window provided and save yourself from the difficulties that you can face after September 30," he had said during his Mann Ki Baat address.

The Centre will soon organise 50 workshops across the country to popularise this scheme and clarify taxpayers' doubts. The government had come up with a similar scheme last year for unaccounted black money abroad and had recovered as much as Rs 2,500 crore, including tax and penalty.