Taiwan's former deputy economic affairs minister Francis Liang has been appointed the island's new envoy to Singapore, ending a protracted search for a replacement to fill the post that has been vacant for five months.

The 65-year-old, who is chairman of the government-funded Taiwan External Trade Development Council (Taitra), is expected to arrive in Singapore by next month to take up his new post.

The Presidential Office announced his appointment yesterday, following speculation in local media last week that he will be picked.

President Tsai Ing-wen had initially appointed former newspaper editor and columnist Antonio Chiang as the trade representative to Singapore. But the 72-year-old resigned in August after he was caught for drink-driving soon after he was sworn in to his new post.

Sources told The Straits Times that staff in the Ministry of Foreign Affairs were notified of Mr Liang's appointment late last week.

Mr Liang, who has been in government since 1978, is a long-serving economic and finance official.

He was Taiwan's chief trade negotiator and played a pivotal role in the inking of some economic deals, including with New Zealand, Japan, China and the European Union. He was instrumental in pushing through a free trade deal between Taiwan and Singapore, signed in 2013.

Observers said with his strong economics background and bipartisan credentials, Mr Liang can help the Tsai administration to promote its New Southbound Policy, which is aimed at doing more business with South-east Asia and reduce Taiwan's reliance on China.

Quoting an unnamed official from the Ministry of Economic Affairs, the Central News Agency said Mr Liang tends to keep a low profile but works hard to keep abreast of new trends in trade.

Legislator Huang Wei-cher said that Mr Liang's appointment will ensure Taiwan's trade diplomacy "will be in safe hands".