Unocal Corp. and Moeco Thailand Co. acquired a combined 20% stake in PTTEP's Arthit gas prospect in the Gulf of Thailand, and PTTEP gained a 10% interest in gas-bearing blocks B and 48/95, off southwestern Viet Nam. Unocal operated the Viet Nam blocks (OGJ Online, Aug. 9, 2000). PTTEP will continue to seek oil field interests, particularly in Iran, Oman, Yemen, and Sudan. Chitrapongse emphasized overseas expansion was crucial to future growth of PTTEP. He also said the company plans to invest 64 billion baht ($1.48 billion) over the next 5 years to boost its natural gas production and support exploration. About 34 billion baht, or 53%, would be spent to raise capacity of Bongkot, Arthit, and Pailin gas fields in the Gulf of Thailand. The remaining 30 billion baht would be used mainly for working capital and interest.