Labour leadership: Lisa Nandy says UK should refuse US trade deal if Trump quits Paris climate accord

Exclusive: 'To take people with us we need to show we’re willing to live our values and stand by them,' says Nandy

Labour leadership hopeful Lisa Nandy will say the UK should hold out on signing a trade deal with the US if Donald Trump carries out his vow to withdraw from the Paris Agreement on climate change.

In a speech in London, the Wigan MP will say Labour should rule out signing trade deals with countries that fail to sign up to the vital climate accords, which committed nearly 200 nations to keeping rising global temperatures below 2C.

The US provoked widespread concern when it gave notice of its intention to leave the agreement last year, saying the 2015 agreement placed an “unfair economic burden” on the US economy.

Ms Nandy will say the UK needs to "call out the behaviour of one of our closest allies" regardless of the economic consequences, as she continues her bid to succeed Jeremy Corbyn at the top of the Labour party.

A post-Brexit trade deal with the US is highly prized by Brexiteers but critics have warned that such an agreement could lead to a lowering of food and environmental standards in the UK.

However ministers have vowed that the UK will not allow the import of chlorinated chicken or hormone-fed beef in the event of a deal with the US. Trade talks will begin in earnest once the UK leaves the EU officially on 31 January.

In a speech to the Royal Society of Arts in London, Ms Nandy is expected to say: "To take people with us we need to show we’re willing to live our values and stand by them. Even when they have economic consequences, or when we have to call out the behaviour of one our closest allies.

"We cannot turn up at the G20 and pledge our commitment to the Paris Agreement while continuing to use government money to invest in fossil fuel projects overseas. Or export plastic waste to dump it in South East Asia.

"As we look to forge new trading alliances across the world, we will need to make choices. We should be clear now: we will refuse to agree any trade deal with a country that has not ratified the Paris Agreement.

"It is easy to blame Trump as a single destabilising force. But the UK should not rest on this as an excuse for lack of action on a global level."

It comes after Ms Nandy's campaign won a boost with an early endorsement by the National Union of Mineworkers (NUM) on Tuesday.

Union support is crucial to the five candidates vying to be leader, as party rules say each candidate must win the support of 5 per cent of constituency parties and affiliated groups, including two trade unions.

Sir Keir Starmer, the shadow Brexit secretary, emerged as an early frontrunner in the race when he won the backing of Unison, the UK's largest union, while Rebecca Long-Bailey is widely seen as the left-wing successor to Mr Corbyn.

Prominent backbencher Jess Phillips and Emily Thornberry, the shadow foreign secretary, both won enough support from MPs to pass the first hurdle, setting up for a five-way contest.

The new leader will be announced at a special conference on 4 April, after being elected by Labour members.

Non-members can apply to be registered supporters – costing £25 – over the next 48 hours, which allows them to vote in the contest.