China and Malaysia signed several trade and investment deals on Tuesday as China denied that it was trying to buy better ties with its southern neighbour.

China is Malaysia’s biggest trading partner but the two countries are often at loggerheads over competing maritime claims in the South China Sea.

Recently, however, Mr Najib has been seen to distance his country from the US as he is caught up in an investigation by US federal prosecutors over claims that billions of dollars were looted from state investment fund1MDB.

Meanwhile, Chinese companies have stepped in to buy assets from the heavily-indebted investment fund, in effect bailing out the Malaysian government.

The agreements signed on Tuesday with China will further invigorate the Beijing- Kuala Lumpur alignment and strain ties with the US. Most significantly, the two nations agreed to a wide ranging naval co-operation deal in which they will jointly develop coastal patrol vessels.

As part of the deal, Malaysia has agreed to buy four Chinese naval vessels, Malaysian state media reported. Two will be built in China and two in Malaysia.

With tensions rising between China and the US in the region, analysts will pay close attention to the deal and whether it signifies a tilt by Kuala Lumpur away from Washington and towards Beijing. It will be the first big purchase of Chinese arms by Malaysia, which currently buys arms from the US and Russia.

Euan Graham, a director at the Lowy Institute in Sydney, said: “It’s a maritime naval purchase, which sends a signal in the South China Sea context, that there now is a strategic element to the relationship that wasn’t there previously.”

Mr Najib’s trip to China follows a thaw in diplomatic relations between China and the Philippines, with President Rodrigo Dutertedeclaring his country’s “separation” from the US on a visit to Beijing this month.

Asked about the Malaysian defence deal, the Chinese spokesman said the agreement provided few details.

The two countries signed 14 agreements in total, including a deal on a high-speed rail link between Kuala Lumpur and Singapore.