Sri Lanka’s imminent victory over the Tamil Tigers owes much to a badly needed injection of arms and aid from China, as well as robust Chinese support at the United Nations, ever since the Government began its new offensive in 2007.

That was the same year that China started building a $1 billion (£660 million) port at Hambantota, on Sri Lanka’s southern coast, that many military analysts suspect it plans to use as a refuelling and docking station for its navy. Beijing says that Hambantota is purely commercial, but US and Indian military planners see it as part of a “string of pearls” strategy under which China is also building or upgrading ports at Gwadar in Pakistan, Chittagong in Bangladesh and Sittwe in Burma.

The strategy, first highlighted in a report commissioned by the Pentagon in 2004, was outlined in a paper by Lieutenant-Colonel Christopher J. Pehrson, of the Pentagon’s Air Staff, in 2006, and again in a report by the US Joint Forces Command in November.

China has no immediate plans to establish a fully fledged naval base at any of these sites but wants a foothold in the Indian Ocean to protect its oil supplies from piracy or blockade by a foreign power, analysts say. The Royal Navy used the eastern Sri Lankan port of Trincomalee in the same way until 1957 and still shares a naval base with the United States on the nearby island of Diego Garcia.

Beijing gave an indication of its naval ambitions in December when it sent three ships on an unprecedented anti-piracy mission to the Gulf of Aden. Then, in January, a Chinese defence “white paper” said that the navy was “developing capabilities of conducting co-operation in distant waters”. China has cultivated ties with Sri Lanka for decades and became its biggest arms supplier in the 1990s, when India and Western governments refused to sell weapons to Colombo for use in the civil war.

Beijing appears, however, to have increased arms sales significantly to Sri Lanka since 2007, when the US suspended military aid over human rights issues. Many of the arms have been bought through Lanka Logistics & Technologies, co-headed by Gotabhaya Rajapaksa, the Defence Secretary, who is also the President’s brother.

In April 2007 Sri Lanka signed a classified $37.6 million deal to buy Chinese ammunition and ordnance for its army and navy, according to Jane’s Defence Weekly. It also bought radar equipment in a separate deal.

More significantly, however, China then gave Sri Lanka, apparently free of charge, six F7 jet fighters last year, according to the Stockholm International Peace Research Institute. The Sri Lankan Air Force urgently needed the aircraft after a daring raid by the Tigers’ air wing destroyed ten military planes in 2007. One of the Chinese fighters shot down one of the Tigers’ aircraft a year later.

Since 2007 China has also encouraged Pakistan to sell weapons to Sri Lanka and to train Sri Lankan pilots to fly the Chinese fighters, according to Indian security sources.

In addition, China has provided crucial diplomatic support in the UN Security Council, blocking efforts to put Sri Lanka on the agenda. It has also boosted financial aid to Sri Lanka, even as Western countries have reduced their contributions.

China’s aid to Sri Lanka jumped from a few million dollars in 2005 to almost $1 billion last year, replacing Japan as the biggest foreign donor. Iran granted Sri Lanka a soft loan of $1 billion and Libya is also poised to give it another of $500 million.

By comparison, the United States gave Sri Lanka $7.4 million in aid last year, and Britain only £1.25 million in humanitarian aid.

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