The European Union has alleged that US authorities are purposefully obstructing a wide-ranging deal to protect EU citizens’ private data during terrorism investigations.

Viviane Reding, the EU’s Justice Commissioner, claims that the US is interested in negotiating individual data sharing agreements with the EU but less inclined to reach an agreement on data protection issues.

"From the outset, we have noted an apparent lack of interest on the US side to talk seriously about data protection," she said this week. "The Americans are visibly standing on the brakes." Reding added that the US has "not even appointed a negotiator" for talks on the subject.

The US has rejected the suggestion that it is deliberately holding up a deal on data protection. “I disagree – we’re moving ahead," William Kennard, US ambassador to the EU, told reporters in Brussels this week.

There are recent cases of the data sharing agreements Reding alludes to. In February 2010, the EU vetoed a scheme that would allow US investigators to tap into SWIFT, a global financial messaging network used by banks and other financial institutions. EU authorities eventually agreed to the proposal after the US said an EU representative could sit in Washington DC and monitor any investigations into the network.

Another example is the EU-US Passenger Name Record Data Transfer agreement, negotiated in 2004 as a response to the 9/11 terrorism attacks in New York. Under this agreement, the US collects, stores and cross-references the personal details of all individuals entering the country against its database of suspected terrorists.