Block 18, a 21,140 sq km concession located off the Batinah coast, was relinquished by the conglomerate's wholly-owned Dubai-based subsidiary, Reliance Exploration and Production DMCC.
The decision follows an exploratory drilling campaign that failed to unearth any significant prospects, the Oman Daily Observer report said.
The move comes six years after Reliance inked a deepwater Exploration and Production Sharing Agreement with the Oman government for Block 18 in the Sohar Basin in June, 2005.
While withdrawing from the concession, Reliance stated that the results of its drilling campaign targeting Block 18 had "not been encouraging".
It estimated the total expenditure incurred on Block 18, as well as another block in East Timor, at USD 177 million, the report said.
State-owned Oman Oil Company Exploration and Production (OOCEP), which had acquired a 30 per cent interest in Block 18 under a farm-out agreement signed in October, 2009, is unlikely to take over the concession and the Ministry of Oil and Gas is expected to remarket the block.
In conjunction with the farm-out agreement, OOCEP also signed a Joint Operating Agreement with Reliance, which provided the basis for setting up a joint operating company to be managed by the two companies upon a commercial discovery being established in Block 18.
Meanwhile, Reliance is currently focused on the development of its sole existing concession in Oman, Offshore Block 41, which covers an area of around 23,800 sq km off the Sharqiya coast.
The company is awaiting the results of 2D seismic surveys before it pursues the next phase of its exploratory plan in Block 41, it said.
Reliance Exploration and Production DMCC's portfolio currently consists of 12 blocks spread across Oman, Yemen, Kurdistan, East Timor, Peru, Australia and Colombia, the report said.