Britain must be ready “to use hard power” and not “walk on by when others are in need”, the defence secretary will say in a major speech this morning.

Speaking at the Royal United Services Institute in London, Gavin Williamson will claim actions by China and Russia have “blurred” the boundaries between peace and war and that the UK “may need to intervene” to honour the “global Britain” mantra.

“The price of non-intervention in global crises has often been unacceptably high. To talk, but fail to act, risks our nation being seen as little more than a paper tiger,” he will say.

Mr Williamson will reiterate a plan to open military bases in Asia and the Caribbean, and will announce that the UK’s new aircraft carrier, HMS Queen Elizabeth, will head to the Pacific region for her first operational tour.

The deployment, likely to be in 2021, will include two squadrons of F35 stealth jets to “stand up to those who flout international law”.

Oct 2018: F-35 jets land on HMS Queen Elizabeth

“Significantly, British and American F35s will be embedded in the carrier’s air wing, enhancing the reach and lethality of our forces and reinforcing the fact that the US remains our very closest of partners.” Mr Williamson will say.

The Conservative politician will use the speech as a rallying cry in an attempt to unite both Remainers and Leavers.

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“It is my belief that Britain has its greatest opportunity in 50 years to redefine its role,” he will say.

“As we leave the European Union, and with the world changing so rapidly, it is up to us to seize the opportunity that Brexit brings.

“We can build new alliances, rekindle old ones and most importantly make it clear that we are the country that will act when required and a nation that people can turn to when the world needs leadership.”

NATO countries must step up and pay their 2% share of spending, he will say, and European countries must “not be distracted by the notion of an EU army”.

“The Alliance (NATO) also must develop its ability to handle the kind of provocations that Russia is throwing at us. Such action from Russia must come at a cost.

Defence Secretary, Gavin Williamson, arrives in Downing Street
‘We must be ready to act and bring others with us,’ Mr Williamson is expected to say

“History has taught us that crisis comes when it is least expected. As uncertainty grows we must be ready to act and bring others with us.”

And in a fast-changing world, Mr Williamson will commit more money to the UK’s cyber defences: “As the cyber threat grows, we are making a very significant additional investment on the £1.9bn we spend on cyber capabilities.

“That’s funding to improve offensive cyber, putting the command and control structures in place across government. And it will give us extra money to protect our networks’ resilience from online attacks.”

He will continue: “Our adversaries are increasingly using cyber attacks, subversion and information operations to challenge us and the rules-based international order.

“I want to see our armed forces embracing transformation at an ever-faster rate, keeping pace with technological change, enhancing our mass and increasing our lethality. We shouldn’t be shy about our ambition for our forces.

“Against adversaries upping their spending and advancing technology, we have to respond. If we do not, we will find ourselves with fewer options when we face threats in the future.”