ONGC to invest Rs 2,600 cr

State-owned Oil and Natural Gas Corp (ONGC) will invest about Rs 2,600 crore in the third phase of development of C-series natural gas fields off the west coast. The company board, in its meeting on March 15, approved advancement of development of C-26 Cluster (consisting of C-23, C-26 and B-12-1) fields of Phase-III development of C-series fields, to pre-monsoon 2014 instead of 2018 envisaged earlier, ONGC said in a statement.