The European Union has adopted a "blacklist" of 17 tax havens, which could mean they lose access to EU funds and face other sanctions.
The decision was made at a meeting of finance ministers in Brussels as EU authorities move to counter tax avoidance and evasion - having urged dozens of nations to make greater commitments to transparency over the past year.
French finance minister Bruno Le Maire confirmed American Samoa, Bahrain, Barbados, Grenada, Guam, South Korea, Macau, Marshall Islands, Mongolia, Namibia, Palau, Panama, Saint Lucia, Samoa, Trinidad and Tobago, Tunisia and the United Arab Emirates were the countries listed.
A further 47 jurisdictions were included in a "grey" list deemed not currently compliant with EU standards though they had committed to change their tax rules, he added.
"We have adopted at EU level a list of states which are not doing enough to fight tax evasion," he said.
The action is aimed at countering disclosures about the behaviour of companies and individuals - the most recent in the release of the so-called Paradise Papers.
EU states launched a process in February to list tax havens in an attempt to discourage setting up shell structures abroad.
While most are legal, there are concerns illicit activities may be being missed.
The EU said it would decide on what measures, if any, were necessary against the territories on the blacklist in the coming weeks.
Luxembourg's finance minister, Pierre Gramegna, said: "To be on a blacklist is in itself bad enough and of course there will be consequences for these countries."
France is said to be pushing for the toughest response.