LONDON — A deal to equip NATO with a fleet of A330 MRTT air-to-air refueling aircraft has been signed by Airbus and OCCAR, the European organization that manages cooperative weapons programs.

Two of the multi-role aircraft have been purchased by the Netherlands and Luxembourg in what is hoped will become a pooling and sharing arrangement, which would also include Belgium, Germany, Norway and Poland.

The Dutch Ministry of Defence (MoD), which is largely bankrolling the initial procurement of aircraft, informed the Parliament in The Hague on July 28 that it had signed a memorandum of understanding with Luxembourg to proceed with the procurement of the two aircraft.

At the same time, OCCAR — operating on behalf of the NATO Support & Procurement Agency — struck a deal with Airbus Defence and Space for the delivery of two aircraft with options for up to six more if other nations join the Multinational MRTT Fleet (MMF) program.

The first two aircraft have been purchased by the Netherlands and Luxembourg but will be the property of NATO.

Poland, Norway and the Netherlands announced in December 2014 they were opening negotiations with Airbus to acquire four A330 aircraft. But to date only the Netherlands among the mainstream military nations interested in the capability has signed up.

A European Defence Agency spokesman said that while the Dutch were now ready to sign, the other nations were not at that stage yet.

"We expect more positive news around October or November [on other nations signing up]," he said.

Some NATO members already have a similar arrangement to pool Boeing Sentry airborne early warning aircraft assets, and earlier this year 15 countries agreed to purchase five Northrop Grumman Global Hawk UAV as part of it's Alliance Ground Surveillance system.

Until the MMF is expanded, the Netherlands and Luxembourg, which doesn't have an air force, will have exclusive user rights, the Dutch MoD said.

The aircraft will be stationed at the Dutch base at Eindoven, and delivery will begin in 2020 — in parallel with the Royal Dutch Air Force decommissioning the two KDC-10 tankers it presently has in service.

The new multi-role aircraft will also help ease capability shortages in cargo lift and troop transport in Europe.

"The purchase of the A330 is an important contribution in addressing the scarce tanker and transport capability of the European Union in particular," the Dutch MoD said.

A study is to be carried out to see whether the European Air Transport Command (EATC), which is also stationed at Eindoven, would supervise the operations of the MRTT aircraft, the Dutch ministry said.

Established in 2010, ETAC pools and shares the air transport and air-to-air refueling assets of seven European nations. The group includes the Netherlands, Belgium, Germany and Luxembourg; but Poland and Norway, who may yet sign up for MMF, are not members of ETAC.

The deal to acquire the A330 comes nearly five years after the European Defence Agency, an arm of the European Union, initiated the program to establish an air-to-air refueling capability among allies in the region as a priority.

The move followed NATO's Libyan air campaign against the Gaddafi regime, which showed up the shortfall in air-to-air tanking across most European alliance members. The US provided 80 percent of the tanking missions during the campaign.

Britain and France are the only European NATO nations with substantial fleets of tanker aircraft. Italy operates four modified 767 tankers.

The British already operate the A330 MRTT, and France is under contract with Airbus to buy a fleet of the jets beginning 2018 to replace its aging Boeing aircraft.

The Dutch MoD said in a statement they were examining the possibility of collaborating with the UK and France on training and maintenance of their jets.