SINGAPORE, July 26 (Reuters) - Thai oil and gas giant

PTT Exploration and Production (PTTEP) has acquired

full ownership of Block A-18 in the Malaysia-Thailand Joint

Development Area (MTJDA) in a $450 million transaction with

Chevron ( CVX ) units.

PTTEP said in a statement late on Friday it signed the deal

with Hess (Bahamas) and Hess Asia Holdings, both now owned by

Chevron ( CVX ) following a recent merger with Hess Corp.

The acquisition gives PTTEP 100% of the outstanding shares

in Hess International Oil Corp, which holds a 50% participating

interest in Block A-18, PTTEP said.

The deal comes as Chevron ( CVX ) restructures globally to

streamline operations and reduce costs, a process that could see

it lay off up to 20% of its workforce by the end of next year.

Chevron ( CVX ) is also seeking buyers for its 50% stake in its

Singapore refinery, Reuters reported in June.

PTTEP said natural gas from Block A-18 is fundamental to

power generation for southern Thailand. The block produces about

600 million standard cubic feet of gas per day, which is equally

distributed to Thailand and Malaysia.

"PTTEP is pleased to further expand our operations in the

MTJDA, which is recognized for its petroleum potential and

strategic significance to Thailand's energy security," Chief

Executive Officer Montri Rawanchaikul said in the statement.

The MTJDA covers 7,250 sq km (2,800 sq miles) in the

southern part of the Gulf of Thailand and is a key source of

natural gas and condensate for Thailand and Malaysia, according

to the statement.