Palau's leader flew into Taiwan on Sunday as the two coronavirus-free allies prepare to launch a travel corridor and boost their pandemic-hit tourist sectors.

A charter flight carrying President Surangel Whipps and a delegation including US ambassador to the country John Hennessey-Niland landed in Taipei for the start of a four-day visit and to kick off what the two sides are billing as Asia's first travel bubble.

"I believe (the travel bubble) will be the first between two, I will call, Covid-free, Covid-safe countries," Whipps told reporters at the airport.

Whipps will meet Taiwanese President Tsai Ing-wen, attend a Palau tourism promotional event as well as visit shipbuilding and aquaculture companies, Taipei's foreign ministry said.

He is set to return to Palau on Thursday with a group of 110 Taiwanese tourists on the first of weekly vacation flights.

The plan is to eventually have 16 flights a week on the route, a major lifeline for Palau's economy, which before the pandemic relied on tourism for more than half its gross domestic product.

Whipps told Taiwan's Central News Agency (CNA) ahead of his visit that "it's important to get tourism back in operation" and demonstrate to the world that the travel corridor can work.

Palau, which lies about 1,000 kilometres (600 miles) east of the Philippines, is one of the few places on Earth never to have recorded a Covid-19 case.

The travel bubble is partly due to Palau's special relationship with Taiwan.

It is one of only 15 nations worldwide to offer Taipei diplomatic recognition in the face of China's long-standing claim that Taiwan is part of its territory.

Whipps said strict measures would be enforced to protect Palau's 18,000-strong population.

Before the pandemic Palau's economy relied on tourism for more than half its gross domestic product
Before the pandemic Palau's economy relied on tourism for more than half its gross domestic product AFP / SEBASTIEN BLANC

Taiwanese visitors must undergo pre-flight coronavirus checks, they can travel only in tour groups and are barred from making individual excursions.

Contact with Palau locals will be kept to a minimum, with tourists staying at designated hotels, eating in separate restaurant areas and allowed to shop only at set times.

Taiwan -- population 23 million -- has been hailed as an example in containing the virus, with fewer than 1,020 confirmed cases and 10 deaths.

Taiwanese officials said the 110 slots in the first tour group to Palau were sold out.

Whipps has acknowledged no system is foolproof but said Taiwanese health authorities had calculated that the chance of Covid-19 reaching Palau via the travel bubble was one in four million.

"We feel that we can now tango. We can work together and feel safe. We trust each other... There is no guarantee that there won't be any Covid. There is no guarantee. However we've done everything to prepare ourselves," he said at the airport.

Democratic Taiwan lives under the constant threat of invasion by authoritarian China, which views the island as its own territory and has vowed to one day seize it.

Beijing has poached seven of Taiwan's diplomatic allies while ramping up military and economic pressure since Tsai's 2016 election win because she rejects its stance that Taiwan is part of China.

Whipps told CNA he had rebuffed Beijing's overtures to switch recognition after he won the presidential election last year.

"I told them, you know, I believe that we should be free to choose who our friends are," he said.

"We value the relationship that we have with Taiwan and nobody should tell us that relationship should be severed."

Palau is among four remaining Asia-Pacific countries that officially recognise Taipei over Beijing, along with the Marshall Islands, Nauru and Tuvalu.