A proposed tourism education bill in Palau will improve environmental protections and crackdown on non-compliant tour operators.
The laws will require operators to advertise the Palau Pledge, a recently introduced environmental commitment, and provide reusable alternatives to disposable plastics, polystyrene cups, water bottles and drinking straws.
Immigration officials will board planes and vessels arriving in Palau and ensure they have signed the Palau Pledge.
Reef-toxic sunscreen will also be banned by 2020, with a fine of $US1,000 and confiscation of goods.
This year Hawaii and a resort in Fiji have announced bans on coral-killing sunscreens, following research into some of the chemicals present in them.
The director of Palau's Tourism Bureau, Kevin Mesebeluu, says Palau is trying to promote green tourism through rewards, but there will be penalties too.
"We're trying to work with the private sector that these changes won't have too much of a drastic effect on their operations, but yes, we have the capability and the power to revoke tour operators' licenses."
The tourism education bill is currently before Palau's house committee.
If it passes, the country's visitors authority will also be asked to set up "an accreditation or rating system" for tour operators and tourism businesses based on their commitment to environmental and cultural protections.
The bill comes as President Tommy Remengesau's government has pushed for "high quality, low volume tourism", amid concerns Palau is being crowded and polluted by unmanageable numbers of tourists.
Tourism is Palau's largest source of revenue but visitor numbers have dropped dramatically following China's ban on its tourism agencies visiting the country.
Chinese tourists have made up 13 percent of Palau's tourists so far this year, compared with 48 percent in 2017.
Experts say the China ban was intended to pressure Koror into cutting its diplomatic ties with Taiwan, in favour of Beijing.