As a result, from 6 am this morning, 95 petrol is selling at B39.32 a litre, 91 petrol at B34.77 a litre and diesel at B26.99 a litre.
The cut in fuel prices was among the election promises made by Prime Minister Yingluck Shinawatra, who also chairs the National Energy Policy Committee.
Initially, the cut will be in effect for six months to a year. It is expected to cause the income of the State Oil Fund to shrink by B6.16 billion a month. The fund, which currently has cash reserves of B15.61 billion and carries debt of B14.61 billion, is estimated to be able to subsidize fuel prices until January next year.
What will happen after that is not clear.