Mumbai, May 21 (IANS): Operators of KG-D6 oil and gas blocks in the Bay of Bengal, Reliance Industries (RIL) and its British partner BP have surrendered two more blocks, reducing their specific assets to four exploration acreages from the original 21.

"During the year, RIL opted to relinquish two blocks KG-DWN-2003/1 and CY-PR-DWN-2001/3 as part of the ongoing effort to high grade its upstream asset portfolio," RIL said in its annual report for 2014-15.

The Mukesh Ambani-led conglomerate said block KG-DWN-2003/1 has been surrendered because of operational restrictions imposed by the defence ministry, while CY-PR-DWN-2001/3 was relinquished "as prospectivity was not commensurate with the high geological risk involved".

"In KG-DWN-2003/1, further progress in petroleum operations was impeded by defence restrictions imposed in October 2012. Since then the JV had continued to seek unrestricted access to the block without success. RIL and its JV partners finally decided to relinquish the block in line with the government's policy," the company reported.

RIL held 60 percent stake in KG-DWN-2003/1 while BP had 30 percent and Hardy Oil, 10 percent. In CY-PR-DWN-2001/3, RIL held 70 percent interest and BP 30 percent.

RIL said its current portfolio includes the producing KG-DWN-98/3, or KG-D6, block in the Bay of Bengal, and the Panna/Mukta and Tapti oil and gasfields in the western offshore.

It also has the western offshore block GS-OSN-2000/1 in partnership with Hardy Oil.