The holiday island of Bali reopened to tourists from select countries Thursday in what Indonesian authorities have called a “baby steps” approach to resuming international travel.

Indonesia closed its borders to foreign travelers some 18 months ago.

Vaccinated tourists from 19 countries — including China, India, Japan, South Korea and New Zealand, as well as parts of Western Europe and the Arabian Gulf — can now travel to Bali and Indonesia’s Riau Islands. Travelers are subject to a five-day quarantine and Covid-19 testing.

The plans are seen as a milestone for the Southeast Asian country’s tourism-dependent islands, which have been crushed by ongoing travel restrictions. Yet several major feeder markets for foreign tourism — including Bali’s No. 1 market of Australia, and neighboring Singapore — were omitted from the list.

Speaking to CNBC Thursday, Indonesia’s Minister of Tourism and Creative Economy Sandiaga Uno said the current policy was based on scientific data and guidance from a panel of epidemiologists. He added that the list would be expanded once data from additional markets supports it.

“We want to make sure that it’s not going to be stop and go, but rather a smooth, incremental basis,” Uno told CNBC’s “Street Signs.”

“[With] Singapore and Australia, definitely, we are continuing to talk,” he said, noting that the conversations are focused on ensuring reopening “will be done first on a safe and secure basis.”

Indonesia’s partial reopening comes as neighboring nations, including Thailand, Singapore and parts of Vietnam, welcome vaccinated tourists from select countries on a quarantine-free basis.

Indonesia — burned by a lackadaisical approach to quarantines which led to a spike in Covid-19 cases in July — is taking a more cautious approach. They have reason, too. The country is gearing up to host the G-20 summit on Bali in 2022.

“It will be purely scientific, making sure that this process will be smooth in terms of the next 18 months as we host G20 events here,” said Uno.

In addition to quarantines, which Uno said would be revised in time, the islands are implementing new safety measures, such as hotel certifications and vaccine boosters.

“We are making sure Bali is prioritizing the whole island to be 100% vaccinated with boosters… in the Q1 of next year,” he said.

Authorities are hoping the new measures will help revive Indonesia’s tourism industry, which accounts for around 4% of the country’s gross domestic product. But Uno acknowledged that reaching pre-pandemic numbers may take time, with visitors likely to opt for less frequent but longer stays in the near term.