Nigel Farage and Reform UK’s chances of winning power could depend on whether Donald Trump succeeds in America, one of Britain’s leading polling experts has said.

Voters across the world are watching the US president to see whether so-called populist politicians can succeed, said Kelly Beaver, chief executive of Ipsos.

His performance will help them decide whether to back similar leaders in their own country, she suggested.

According to Ms Beaver, growing numbers of voters are losing faith in traditional political parties and believe that governments have stopped being able to deliver higher living standards. Voters are increasingly willing to “roll the dice” on insurgent politicians, she said.

Referring to the Reform UK leader and to French politician Marie Le Pen, whose National Rally party has enjoyed a surge of support in France, she said: “In the UK Nigel Farage, Marie Le Pen in France. These are not people who’ve popped up yesterday, they’ve been around for some time, they’ve established themselves, and the public are at the point where a good proportion are saying ‘actually actually I’m happy to take a bit of a risk’.”

However Mr Trump would now provide evidence showing whether the risk was likely to pay off, she said in an interview with Labour MP Liam Byrne.

“They’re going to have a moment now where they can actively see one very dominant populist leader with some very clear policy ideas. So they’ve got Donald Trump in office now in the US, and for many populist leaders around the world and indeed many citizens who may have voted that way, they will be looking to see what can be delivered.

“Are these policies actually going to deliver what they have been articulated during the election campaign and by those leaders? So there’s going to be a moment, a sort of proof point with populism written large at scale in the US.

“And some of the things that we’re seeing around trade policies and immigration policies coming out of the US, are they going to deliver or are there going to be unintended consequences and what will that do to popular sentiment around the world?”

Recent polls have suggested support for Reform is roughly equal with the other parties. A survey by Techme found that 26% of voters would back Labour in a general election today, with 25% supporting Reform and 22% voting Conservative.

Mr Trump’s right-hand man, vice-president JD Vance, last week delivered a speech in Munich saying the US and Europe – including the UK – faced similar challenges, such as excessive levels of immigration and a failure to defend free speech.