Under the initial agreement, Europe allowed the US to keep passenger data for up to three and a half years, but the US wants to be able to hold onto the information longer.
The US also wants to be able to share the data freely with other counter-terror agencies whereas Europe wants this to be possible only on a restricted, case-by-case basis.
Although both sides appear to be getting closer to clinching a deal, the failure to reach an agreement before the ECJ deadline leaves carriers in a legal limbo.
"There is no agreement. There is a legal vacuum as of midnight tonight," Commission spokesman Jonathan Todd said on 30 September.
In the meantime, the United States has warned it could take steps, including fining airlines €4,700 per passenger or revoking landing rights, if data are not turned over.



