A Japanese ban on charter flights operated by Thai airlines remained in place on Thursday as talks to lift the ban continued between the two countries, a senior Thai government official said.

Japan, along with South Korea and China, has banned Thailand-registered airlines from flying new charters and new scheduled flights to their countries because of safety concerns highlighted by an international audit.

Thailand's transport minister had said on Wednesday that Japan would sign a memorandum of understanding with Thailand's Department of Civil Aviation (DCA) on Thursday to temporarily lift the charter flight ban for Thai airlines during April and May.

But Somchai Piputwat, director general of the DCA, told a news conference on Thursday that Thailand-based airlines are still not permitted from making charter flights to Japan until the negotiation is complete.

Japan's Civil Aviation Bureau has sent negotiators to Thailand and hopes the two sides will reach agreement on Friday, Somchai said without giving details about the discussion.

Nearly 120,000 travelers seeking to fly to Japan in the next two months were expected to be hit by the ban, which affects national carrier Thai Airways International and long-haul, low-cost carriers like Thai AirAsiaX and NokScoot.

Thailand's Department of Civil Aviation has re-evaluated licences of Thai airlines flying to Japan and South Korea, two major destinations for Thai travelers to ensure compliance with international standards, Somchai said.

Thai Airways is seeking permission to fly 14 charter flights to Japan, while its unit Thai Smile is also aiming to open new flights to Japan, he added.