Lithuania and Poland will each assign a brigade to the NATO headquarters in Poland to "train and act together" for the defence of the Suwalki Gap.
The Suwalki Gap connecting Lithuania with Poland is just 80 kilometres wide, and is flanked by Russian exclave of Kaliningrad and Belarus. NATO has stressed that if the corridor was seized during an armed conflict, the Baltic states would be cut-off from the rest of the Alliance.
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In Vilnius, the two countries on Wednesday signed an act of affiliation between Lithuania's Iron Wolf Mechanised Brigade and Poland's 15th Mechanised Brigade and have assigned them to the NATO's Multinational Division North East headquarters, with the task to "train and act together in order to protect the Suwalki Gap".
The brigades will remain under the command of their respective countries, but the NATO headquarters will be able to train with them in joint military exercises.
"We are going back to mechanisms and cooperation proven over centuries. We are heading toward something we had before the Battle of Grunwald [in 1410] or the Battle of Orsha [in 1514]," Lithuanian Defence Minister Raimundis Karoblis told reporters after the meeting with his Polish counterpart Mariusz Błaszczak on Wednesday.
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The battles in the 15th and 16th centuries saw joint Lithuanian, Polish, and allied forces defeat the Teutonic Order and the Grand Duchy of Moscow, respectively.
The cooperation agreed on Wednesday will also step up interoperability with Poland, "one of the most reliable Lithuania’s allies in security and defence, as well as with other NATO allies," according to the Lithuanian Defence Ministry.
The Lithuanian–Polish defence council was endorsed on February 21, 2019 by the presidents of both countries, and it met for the first time in Vilnius on Wednesday.
The ministers also discussed the cooperation of the respective armed forces, possibilities to integrate national airspace and defence systems, and the need to retain a continuous US presence in the region.
"[The agreement] will allow us to organise more joint exercises, coordinate defence plans and cooperate even closer on defence and security," said Błaszczak.
"Joint exercises [and] operational plans are all things that ensure security," he added.
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Suwalki Gap and Poland's F-35s
"Just as the Fulda Gap could be defended during the Cold War, the Suwalki Gap can and will be defended, too," said Lithuanian Army Colonel Darius Vaičikauskas, the chief of staff at the multinational division headquarters in Elblag, Poland,
The Fulda Gap was an area in West Germany that was seen by NATO as an obvious route for a Soviet tank attack during the Cold War.
"[The agreement] is a symbolic act between the two countries, and those unfriendly to us probably already know what that means and can mean to them," the colonel said.
Meanwhile, Lithuania's Chief of Defence Lieutenant General Valdemaras Rupšys welcomed Poland's decision to purchase advanced F-35 fighter jets, saying this will add to the security of the region as a whole.
"There are no borders between NATO countries. There is no border that could stop this plane," he said.
The Polish defence minister will sign a contract to purchase the F-35 fighter jets on Friday.
CORRECTION: The earlier version of this article incorrectly stated that the affiliation agreement between Lithuania's Iron Wolf Brigade and Poland's 15th Mechanised Brigade will include establishing a separate unit.
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