New Delhi, Aug. 13 -- ExxonMobil signed a deal on Tuesday to explore a vast area near Trinidad and Tobago for oil and gas, even as the twin-island nation faces pressure to focus more on green energy deals.

The search will take place off Trinidad's east coast, in a region that spans more than 2,700 square miles (7,000 square kilometers) and is more than 6,500 feet (2,000 meters) deep, according to government officials.

The deal was signed following six months of negotiations that were held at a record pace, said John Ardill, ExxonMobil's vice president of global exploration.

There are "no guarantees of success," Ardill cautioned during the ceremony. "But many of the largest discoveries and developments in the world are occurring in deep...