* Thailand to hold auctions for natural gas fields in Dec
* Auction expected to take 7 months with winners announced in mid-2018 (Adds background.)
BANGKOK, Nov 7 (Reuters) - Thailand's government expects to hold an auction for the Erawan and Bongkot natural gas fields in December after two delays, a senior government official said on Tuesday.
The government is currently drafting the terms of the auction and the production sharing agreement, Veerasak Pungrassamee, director-general of the mineral fuels department told reporters, adding that the auction terms should be approved by November and announced in December.
The auction process is expected to take seven months and winners will be announced in the middle of 2018, he said.
Chevron Corp operates the Erawan field while state-owned PTTEP operates the Bongot field under licenses which are set to expire in 2022 and 2023 respectively.
The areas have combined output of 2.2 billion cubic feet a day, about 76 percent of gas output from the Gulf of Thailand.
Thailand's PTT Exploration and Production said in a statement last week that it would participate in "the bidding process of expiring concessions in the Gulf of Thailand, including the Bongkot and Erawan concessions."
Reporting by Chayut Setboonsarng; Editing by Christian Schmollinger and Amy Sawitta Lefevre