GETTY Japan are planning to convert an Izumo helicopter carrier into a fighter jet carrier

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The 248-metre long carrier would be the first Japanese vessels capable of launching warplanes since the Second World War, marking a continuation in Japan’s recent militarisation. Following its defeat at the end of the Second World War Japan signed a deal promising not to build any offensive weapons and to convert its military into a defensive force. Now Japan’s navy, known as the Maritime Self Defence Force, has drawn warnings from China after appearing to be moving away from the peace agreement.

Chinese foreign ministry spokesman Hua Chunying said: “We urge Japan to do more that may help enhance mutual trust and promote regional peace and stability.” China has warned the move may violate Japan’s constitutional “no-war” clause. Prime Minister Shinzo Abe has already drawn criticism after signing arms deals including one with the US to buy 42 F-35A.

The F-35A needs a runway and would be unsuitable for a converted Izumo-class carrier, however, it has been suggested that the order could be altered to include F-35Bs which are capable of vertical take off. Local media has put the price of conversion at £372million ($500million) a figure which would rocket to £3billion ($4billion) if a similar ship, the Kaga, was added. It is expected that the carrier would patrol disputed areas of the East China Sea where China and Japan both claim sovereignty over the Senkaku Islands.

Discover the disputed islands of the South China Sea Wed, May 10, 2017 Among the islands at the heart of territorial disputes in the South China Sea. Play slideshow Getty Images 1 of 6 Subi Reef at Spratly Islands: Subi Reef has transformed from a single building and cranes on an artificial sand bank to what looks look a forward operating base with its own town.

The expansion comes after it was revealed Japan is building missile batteries on an island near China. The move is part of a military expansion that will see anti-ship and anti-aircraft cruise missile batteries joined by troop garrisons and radar installations installed on Japanese islands. The fortification comes as Beijing has aggressively sought to extend its power in the South China Sea to wrestle control of shipping lanes and islands from other nations.

GETTY China and Japan are locked in dispute over the sovereignty of the Senkaku Islands