Staff came to see Krissada at the office, offering him flowers to boost his morale, ThaiPBS reported.

Krissada said he had not been pressured by the station’s policy committee to step down, and urged staff to carry on the station’s professional principle of serving the public.

The policy committee chairman Jumpol Rodkamdee said recent events provided a crucial reason for the station and its staff, especially the committee and the station’s executives, to work more closely to forge an understanding in the station’s policies and operations to prevent similar problems in the future.

The controversial investment has raised public concerns whether the integrity and good governance of the public broadcaster was compromised. ThaiPBS subscribed to CPF debentures worth Bt200 million.

“The director resigned in order to take responsibility [for the investment],” a statement issued by ThaiPBS on Wednesday night said.

Krisda announced his resignation during an emergency meeting of the station’s policy committee for reviewing the controversial investment on Wednesday night.

He earlier defended the station’s investment decision, saying the annual Bt2-billion budget from “sin taxes” was not enough to run the station.

Before announcing his departure, ThaiPBS on Wednesday afternoon issued a statement, saying it would review its investment framework in the capital market and cease investments in some companies, without mentioning specific companies.

ThaiPBS executives said in the statement that they regretted the investment decision and wished to apologise to the public if their decision to purchase the debentures caused concern.

The purchase, they said, was aimed at maximising the financial management of the organisation and adhered to its policy framework.

However, to demonstrate that ThaiPBS listens to the public, it will review its policy framework concerning investments and cease investments in some companies, the statement said.

The announcement on its website said that the matter would be submitted to its policy committee soon.

Deputy Prime Minister Wissanu Krea-ngam said on Wednesday that he would send a letter to ThaiPBS to ask for more information regarding its investment in debentures from CPF. Prime Minister Prayut Chan-o-cha also responded to the issue, saying concerned officials would attend to the matter.

Somkiat Tangkitvanich, a drafter of the law setting up Thai Public Broadcasting Service in 2007, on Tuesday suggested on Facebook that the station should review its investment from an ethical aspect. He added, however, that public broadcasting law did not prohibit the station from investing in the market.