NEW DELHI (REUTERS) - A scheduled Indian Supreme Court hearing involving the Sahara conglomerate, whose chief has been in jail over the group's failure to comply with a ruling to repay billions of dollars to investors in outlawed bonds, will not be held on Tuesday.

The reason for the court not hearing the case on the scheduled date was not known, two lawyers involved in the case who declined to be identified. They added they did not know when the case would be heard next.

Sahara Chairman Subrata Roy, 65, was arrested on February 28 for failing to appear at a hearing in the long-running legal battle between the unlisted group and the Indian securities regulator, and has been held in a Delhi jail since March 4.

The court, which had ordered Roy to be held until the next hearing, had also asked Sahara to come up with a "concrete and acceptable" plan to refund investors.

Last Tuesday, the court rejected a Sahara proposal to give bank guarantees of 225 billion rupees (S$4.7 billion) within three to six months, as well as a subsequent proposal to pay a total of 174 billion rupees in six instalments through July 2015.

Sahara is best known as the former main sponsor of India's national cricket team, as well as owner of New York's Plaza Hotel and London's Grosvenor House. It has a net worth of $11 billion and more than 36,000 acres of real estate, according to its website.