A European Parliament committee has voted to reject a deal under which EU states will hand over air passengers' details to the US to fight terrorism.
Passenger details will be sent to the US soon after take-off
The committee says the deal does not offer adequate privacy protection.
In two weeks, the European parliament will vote on the accord, which allows data to be taken from booking records.
If the commission goes ahead with the measure despite a parliamentary vote against, MEPs can take the matter to the European Court of Justice.
The parliament's civil liberties committee voted by a large majority to condemn
the European Commission for agreeing to pass on data.
"The agreement with the United States is not on a level
that... gives enough protection to EU citizens," said Dutch
Liberal Democrat Johanna Boogerd-Quaak, who wrote the resolution.
The parliament's opinion has no legal force, but the
commission will find it difficult to ignore such a strong
political signal from the EU's elected assembly, officials say.
The EU and the US have agreed a deal on sharing data on all airline passengers crossing the Atlantic.
It means that most personal details given at check-in will be sent to the US as soon as passengers leave Europe.
The details will include a wide range of information, such as addresses, phone numbers, date of birth, credit card numbers, how many people are travelling together and how many bags they are carrying.
The US has agreed to use the data only in fighting terrorism and related crimes but not for ordinary crimes as Washington had initially requested.
After three and a half years, Brussels and Washington would jointly review the system.