Theresa May has warned an EU-wide deal on sharing air passenger records must be struck immediately in the wake of the Paris terror attacks.
The Home Secretary also said more action was needed to halt the flow of firearms as she arrived for talks with her European counterparts in Brussels.
Calls for greater cross-border collaboration intensified after the massacre of 130 people in the French capital, which fuelled concerns that extremists are passing unchecked into Europe from Syria and Iraq.
Interior ministers are meeting today to discuss long-delayed measures relating to information on air travellers.
Britain has been pushing for an agreement on the Passenger Name Records (PNR) directive for years.
PNR data covers information provided by passengers and collected by air carriers during reservation and check-in, and can include travel dates, contact details and payment information.
Access to the data is seen as an important tool for authorities in identifying previously unknown suspected terrorists and serious criminals.
Under the proposals carriers operating flights covering at least one EU country would be obliged to send PNR data to authorities, while member states would share alerts created from the processing of the information. When they were first mooted, the plans were rejected by MEPs in 2013.
Arriving at the discussions today, Mrs May said: "Challenges in relation to security and the Paris attacks remind us of the need to maintain our domestic security.
"Europe today must come together, must work further together to increase the sharing of information across borders and passenger name records is important in this.
"We have been waiting too long for a deal on passenger name records. We need a deal now, immediate action is important.
"But we also need to do more to stop the trafficking of firearms and deal with the movement of firearms across the EU."
She said the UK has "stood shoulder to shoulder with France" since the Paris attacks.
The Home Secretary added: "The decision that was taken this week by a clear, cross-party parliamentary majority in the UK to start air strikes in Syria is a sign of the determination of the UK to deal with this terrorist threat and to keep people safe.
"But as we see those air strikes taking place in Syria, as we strike at the heart of Daesh (Islamic State), we must of course remember the challenges that we face here at home in Europe."