BRUSSELS (Reuters) - The Netherlands, Poland and Norway are to negotiate with Airbus (>> AIRBUS GROUP) to buy four military in-flight refuelling planes, European defence officials said on Friday.

The three countries are interested in buying a variant of the Airbus A330 that can be used for aerial refuelling, as well as for passenger transport, strategic airlift and medical evacuation operations, the European Defence Agency (EDA), the European Union's defence arm, said.

The Dutch government, leading the initiative to plug a gap in Europe's aerial refuelling capacity, said the consortium wanted to acquire four aircraft.

Other European countries have previously expressed an interest in the initiative and the number of nations and aircraft involved could increase later, Peter Round, EDA's director of capability, armament and technology, said.

Four aircraft was "a base line", he told Reuters.

The announcement means Boeing (>> Boeing Co) has effectively been ruled out of the contest to supply the planes since the European consortium had asked for information on products and pricing from both Airbus and Boeing earlier this year.

"The three nations have identified that only one military off-the-shelf solution met their key requirements in terms of capabilities and timeframe," an EDA statement said.

Round said a contract was expected to be placed early in 2016 with the planes starting to be delivered late in 2018 or early 2019. The aircraft will be operated jointly by the three countries and may be based at Eindhoven in the Netherlands.

EU leaders have identified increasing Europe's aerial refuelling capacity as a priority. European states were forced to rely heavily on the United States for refuelling during the 2011 Libyan war.

Russia's annexation of Crimea has led NATO and the United States to step up calls for Europe to halt years of defence spending cuts and strengthen their armed forces. Sharing capabilities is seen as a cost-effective way of doing this.

Ten European countries agreed in 2012 to work together to boost their military airborne refuelling capacity.

Five of those countries, which were then interested in buying eight to 10 military refuelling planes, approached Airbus and Boeing for more information earlier this year.

Round said countries operated on different defence procurement cycles and EDA did not want to hold up the programme waiting for each country to make up its mind.

So three countries were initially moving forward.

"But that doesn't mean the others have gone. It just means they are not ready to throw their hat straight into the ring right now," he said.

(Editing by Greg Mahlich)

By Adrian Croft

Stocks treated in this article : AIRBUS GROUP, Boeing Co