What is really going on in politics? Get our daily email briefing straight to your inbox Sign up Thank you for subscribing We have more newsletters Show me See our privacy notice Invalid Email

Theresa May tonight launched a stinging attack on Donald Trump minutes before a face-to-face meeting with the US President.

The Prime Minister railed against his decision to pull America out of the Paris climate change deal and blasted nations which erect trade barriers and pursue protectionism.

Addressing the United Nations General Assembly in New York, Mrs May issued slap downs to Mr Trump, Russian president Vladimir Putin and North Korean dictator Kim Jong-un.

Leaders who fail to respect international agreements risk jeopardising faith in institutions, she warned.

Delivering a thinly-veiled rebuke to the US President, she said climate change “is depleting and degrading the planet we leave to our children”.

And the PM hit out at countries which try to stifle global trade, after Mr Trump's “America first” inauguration speech in January.

She warned against moves which “undermine support for the forces of liberalism and free trade that have done so much to propel global growth”.

(Image: AFP) (Image: REUTERS)

Inequality was “pushing some countries towards protectionism in the belief that this best defends the interests of their own people”, she claimed.

Mrs May added: “If this system we have created is found no longer to be capable of meeting the challenges of our time, then there will be a crisis of faith in multilateralism and global co-operation that will damage the interests of all our peoples.

“So those of us who hold true to our shared values - who hold true to that desire to defend the rules and high standards that have shaped and protected the world we live in - need to strive harder than ever to show that institutions like this United Nations can work for the countries that formed them, and for the people who we represent.”

She called on nations to ensure “that those who flout the rules and spirit of our international system are held to account; that nations honour their responsibilities and play their part in upholding and renewing a rules-based international order that can deliver prosperity and security for us all”.

The PM added: “As the global system struggles to adapt, we are confronted by states deliberately flouting – for their own gain -the rules and standards that have secured our collective prosperity and security.”

Video Loading Video Unavailable Click to play Tap to play The video will start in 8 Cancel Play now

(Image: REX/Shutterstock) (Image: PA)

In a wide-ranging speech, Mrs May issued a damning assessment of the UN, saying that “throughout its history the UN has suffered from a seemingly unbridgeable gap between the nobility of its purposes and the effectiveness of its delivery”.

The 193-member body has a "regular" annual budget of $2.7billion (£2billion), as well as spending $7.3billion (£5.4billion) on peacekeeping, more than $15billion (£11billion) on development, and over $14billion (£10.3billion) on humanitarian action.

It sends 100,000 peacekeepers to 13 missions.

This year the UK will pump £90million into the regular Budget, make £2billion in voluntary contributions, and provide 700 peacekeepers.

But Mrs May threatened to split cash from UN programmes that fail to produce results.

Demanding sweeping reforms to the crisis-hit 72-year-old institution, she said: “The UN and its agencies must win our trust by proving to us and the people we represent that they can deliver.

“That is why we will remain generous in our funding but set aside 30% to be paid only to those parts of the UN that achieve sufficient results.”

She also urged China not to block UN efforts to bring North Korea to heel.

Warning of the “immediate, global danger” posed by Kim Jong-un as he continues to develop a nuclear bomb, which has tipped the region towards the brink, Mrs May told world leaders: “Time after time he has shown contempt for the international community of law abiding states, contempt for his neighbours, and contempt for the institutions and rules that have preserved peace and security.”

Video Loading Video Unavailable Click to play Tap to play The video will start in 8 Cancel Play now

The PM praised UN attempts to clamp down on Pyongyang, but added: “Unless all Security Council members continue to live up to the special responsibilities that are placed upon us and, in seeking to resolve this crisis, be prepared to take all necessary measures to tackle this threat, we will not be able to bring stability to the Korean peninsula.”

Beijing stands accused of watering down sanctions against the pariah state, and has faced mounting pressure to rein in Kim.

But the dictator continues to press for a nuke, believing it will protect him from any US-backed bids to topple his regime.

Mrs May also delivered a slap down to Vladimir Putin, who has not attended the Assembly.

Without naming Russia, she accused Moscow of blocking key Security Council resolutions over Syria.

“One country in particular has used its veto as many times in the last five years as in the whole of the second half of the Cold War – and in so doing they have prevented action against a despicable regime that has murdered its own people with chemical weapons,” she said.

Meeting at New York's Lotte Palace Hotel, Mr Trump and Mrs May shook hands and sat in front of US and UK flags, with a small coffee table with flowers on it between them.

Speaking in his home city, The President said: "It's great to have Prime Minister May from the UK and her representatives who are people who we know very well.

poll loading Does May's 'stinging attack' make you like her more? 0+ VOTES SO FAR Yes No

"We will be doing a lot of trading with the United Kingdom and we look

forward to it.

"We've gotten to know each other over the last period of a year and it's a real honour to have you here."

The PM said: "It's good to be here and as you say we've had many discussions between our representatives and ourselves on a whole variety of issues, including trade, which is important for us, and some other policy issues and our security and defence relationship which of course is the closest we have."