Rishi Sunak hails Britain’s global alliances as its “greatest source of strength and security” as he prepares to travel to America to meet Joe Biden.

The Prime Minister flies to San Diego, Californiaon a trip today to hold talks with the US president and hammer out a major defense deal.

Mr Sunak and Mr Biden will be joined by the Prime Minister of Australia Anthony Albanese to discuss the purchase of nuclear submarines under the Aukus pact between Great Britain, the United States and Australia.

As well as the hope that Mr Albanese will announce the purchase of a British-built fleet, Mr Sunak’s visit will also be used to present a new comprehensive review of defense and foreign policy.

It was updated in the wake of Russia’s invasion of Ukraine and should provide an updated perspective on Britain’s approach to threats from Moscow and China.

Mr Sunak and Mr Biden will be joined by Australian Prime Minister Anthony Albanese to discuss the purchase of nuclear submarines under the Aukus Pact

Mr Sunak’s visit will also be used to launch a new integrated defense and foreign policy review, with the prime minister under pressure to take a tougher stance towards Beijing.

Mr Sunack has been under pressure from Tory MPs to take a tougher stance on Beijing.

His predecessor, Liz Truss, had intended to declare China a “threat” to Britain’s national security in an updated comprehensive review.

Since becoming prime minister, Mr Sunak has advocated a softer approach and has seen Beijing as little more than a “systemic challenge”, angering some backbench conservatives.

But it emerged that the updated integrated review, which Mr Sunak will publish tomorrow, will include a reference to the threat China poses to Taiwan.

In accordance with TelegraphIn response to recent warnings from the House of Commons foreign affairs committee about the dangers of a Chinese invasion of Taiwan, the government has responded by revising the document to include the island’s democracy.

However, the move may still not be enough to placate Tory MPs.

Former Conservative leader Sir Iain Duncan Smith told the newspaper he wanted to see “a reversal in the government’s policy towards China”.

“I want the government of which Rishi is the prime minister and leader to accept what he said when he ran for leadership, that China is a systemic threat,” he said.

“The government needs to make a decision about China and stop sitting on the fence.

“They’re threatening to invade Taiwan, and we’re not saying anything very important about it.”

Ahead of his trip to the US, the Prime Minister said: “In troubled times, the UK’s global alliances are our greatest source of strength and security.

“Today I travel to the United States to launch the next phase of the Aukus nuclear submarine program, a project that will connect our closest allies and provide security, new technology and economic advantage to the country.

“As we launch the 2023 Refresh integrated review tomorrow, this is the future we want to deliver – a Britain that is safe, prosperous and standing shoulder to shoulder with our partners.”

Mr Sunak met French President Emmanuel Macron last week, patching up relations after they hit a low point with the September 2021 signing of the Aukus deal, which saw Australia abandon France in favor of a deal with Britain and the US.

Negotiations over the past 18 months have left the Canberra government facing a choice between a British and an American design.

Australia could reportedly opt for a modified version of Britain’s Astute-class submarine, filling the gap until it enters service in the 2040s alongside the five US Virginia boats.

The UK hopes Aukus will lead to work for UK shipyards such as BAE Systems’ facility in Barrow-in-Furness, Cumbria.