 On 15 February 2005, PETRONAS awarded two Production Sharing Contracts (PCS) to Shell and PETRONAS Carigali Sdn Bhd for the ultra-deepwater Blocks ND6 (formerly Block Y) and ND7 (formerly Block Z) off the east coast of Sabah, encroaching into Indonesian-claimed Ambalat.The two blocks which are the main cause of the conflict are 
ND6 Block covers an area of about 8,700 square km, where partners will acquire and process 1,700 square km of new 3D seismic data and drill three wildcat wells with minimum financial commitment for the block at US$37 million.ND7 Block has an area of about 17,000 square km.