NATO fighter jets will continue to patrol the skies over Lithuania, Latvia and Estonia until 2018.

A NATO official and officials from the Baltic nations announced the deal Wednesday.

The three countries joined the NATO alliance and the European Union in 2004, but lack the resources to patrol their own airspace. NATO warplanes from various member states have been providing assistance, rotating squads of four fighter jets through an airbase in northern Lithuania.

Officials from Lithuania, Latvia and Estonia – which border on Russia – had been pushing to make the arrangement permanent.

NATO Secretary-General Anders Fogh Rasmussen welcomed the the decision, saying it “exemplifies the kind of cooperation among allies that will become increasingly important in the future, as we reconcile our security requirements with budgetary realities.”

Relations between NATO and Russia have been fragile, with Russia continually opposing the alliance's plan to build a missile defense shield in Europe.

NATO and the U.S. say the system is intended to help deter threats from countries such as Iran.