Aug 12 (Reuters) - Exxon Mobil ( XOM ) could invest as

much as $21.7 billion in Trinidad and Tobago if the energy major

finds reserves in a large deepwater area it plans to explore for

oil and gas in the Caribbean country, energy minister Roodal

Moonilal said.

The official spoke on Tuesday at an event in Port of Spain

to sign a production sharing contract with the company that will

mark its return to the country.