The Election Commission (EC) on Tuesday endorsed Chadchart Sittipunt as the winner of the May 22 Bangkok governor election.
The EC also certified the victories of five more city councillors after endorsing 40 on Monday, raising the total to 45 out of 50.
Mr Chadchart, 56, the former Pheu Thai heavyweight who ran as an independent, was elected with a record-breaking 1.38 million votes on May 22.
But by Monday, the EC had yet to endorse his victory, saying it needed to investigate complaints about alleged irregularities in the gubernatorial election before making its decision. The EC on Monday only endorsed the result of 40 Bangkok councillors.
Activist Srisuwan Janya registered several complaints with the EC against Mr Chadchart.
Mr Srisuwan accused Mr Chadchart of having a hidden agenda of vote buying by designing campaign posters in a way that they could be converted into shopping bags or aprons. The activist also accused him of breaking the law by attacking the bureaucracy in his campaign speeches.
Mr Chadchart called on his supporters not to put pressure on the EC to certify his victory.
Media reported that the 1444 EC hotline received a huge number of phone calls from people on Monday wanting to know if Mr Chadchart’s victory would be endorsed.
