Tevin Vongvanich only took the helm in May at Thailand's top oil and gas explorer, PTT E&P , but he is already overseeing a multibillion dollar M&A deal as part of the company's mission to pursue acquisitions and ramp up production.

PTT Exploration and Production (PTTEP) is set to complete a $1.9 billion takeover of London-listed Cove Energy this week, having trumped global oil titan Royal Dutch Shell in a five-month bidding war.

The acquisition -- PTTEP's first since Tevin became chief executive -- will give the state-controlled firm access to massive gas finds off the coast of east Africa and boost energy supplies for Thailand, which uses natural gas to generate 70% of its electricity.

Tevin, an energy sector veteran known for his experience in finance, has said he will continue to scout for opportunities to buy assets overseas as part of PTTEP's plans to triple production to 900,000 barrels of oil equivalent per day by 2020.

"It's a mission that we have to accomplish," Tevin, 54, told Reuters last month. "We are looking to buy assets everywhere where there is potential."

To finance its takeover of Cove, PTTEP said it plans to raise $3.1 billion in Thailand's biggest share sale, sending its shares to a six-week low on Monday on investor concerns of a dilution to earnings.

Bangkok-born Tevin had previously worked at PTTEP for 15 years before moving to parent PTT, Thailand's top energy firm, where he rose to become chief financial officer.

Now, as head of the flagship exploration company of the PTT group, the soft-spoken Tevin is among the top decision-makers as the company sets about its business of securing energy supplies for Thailand.

"It's a challenge for him," said an energy analyst who asked not to be named. "Tevin is like a good-grade student who always gets his assignments done nicely. But this will be a tough one."

Tevin, however, is no stranger to the world of deal-making. As CFO at PTT, he playing a key role when the company acquired Australia's Straits Resources in 2009, the group's first foray into the coal business and its second investment in Australia.

Before that, he played a part in 2005 in the complicated restructuring of Thai Petrochemical Industry (TPI), which was the country's largest corporate debtor when it collapsed under a mountain of foreign debt in the 1997-1998 Asian financial crisis. TPI was renamed IRPC and became part of the PTT group.

Tevin has said he was inspired to enter the energy business when natural gas was discovered in the Gulf of Thailand in the 1970s, but it was also in his blood: his father worked at Esso, a Thai unit of ExxonMobil.

Tevin, a father of three and a jazz lover, started his career as an engineer with energy explorer Unocal, which was later acquired by Chevron.

He also has extensive overseas experience, having earned a Master's degree in petroleum engineering from the University of Houston and another in chemical engineering from Rice University. He completed a global leadership programme at Harvard Business School.