JAKARTA, July 18 (Reuters) - The Indonesian unit of ExxonMobil on Tuesday said the company "no longer wishes to continue further discussions or activity" involving the East Natuna gas block in the country.

The firm's Vice President of Public and Government Affairs Erwin Maryoto told Reuters in an email the decision was taken after completing a "technology and market review".

The East Natuna field is believed to hold one of the world's largest untapped gas reserves. State energy firm Pertamina had expected to sign a production sharing contract with Exxon and Thailand's PTTEP for the project last year.

"We remain committed to our Indonesia operations and continue to seek and evaluate new opportunities in the country," Maryoto added.

(Reporting by Wilda Asmarini; Writing by Gayatri Suroyo)