Ariya Tiranaprakit, executive vice president of ThaiBMA, told Krungthep Turakij that the net-sell position was a result of the tapering in the US bond-buying programme.
She said that the oustanding amount showed the annual decline for the first time in recent years.
The association's rate survey showed that 11 of 13 dealers are convinced that Thailand's policy rate should remain at 2.25 per cent through the end of this year. The other two foresee a rate cut, if political impacts on the economy increase.
In the first 9 trading days of this year, ThaiBMA found that foreign investors have shifted investment to short and medium-term bonds, which has pressured the Thai bond yield by 0.10 percentage point. Foreign investors had remained the net-buyer, despite intensifying political situation.
On January 14, foreign investors bought Bt4 billion net of Thai bonds.