Two of the founders of the leftwing pressure group Momentum are to launch a campaign asking British volunteers to back a campaign for free healthcare in the US by telling Americans about the benefits of the NHS.

The idea is to sign up activists who are prepared to talk up the British healthcare system as a good example of how a campaign such as “National Medicare For All” in the US would work. It comes as part of a campaign by America’s National Nurses United union.

Emma Rees, one of the original four Momentum organisers, said: “We are looking for people who want to help in the fight to build a public healthcare system in the US – they may well be people who are also concerned that it is under threat in the UK.”

Rees and her colleague Adam Klug ran six trial phone banks in October, and she says that “while not every call is going to be successful” Americans were at least willing to listen to Britons trying to engage with them.

“We’re talking about universal healthcare for all Americans; it’s not as intrusive as asking people who they are going to vote,” Klug adds. “What we’re talking about here is a human right.”

They want Britons to join in with the NNU’s National Medicare for All week of action, running from 9-13 February. NNU is the largest unionrepresenting bedside nurses in the US.

Rees and Klug work for The Social Practice, which was set up by Becky Bond, a senior adviser to Bernie Sanders’ unsuccessful bid for the Democratic nomination in 2016, having met her in 2017 after two years helping run Momentum.

They are part of a growing network of young British leftwing activists forging links with their counterparts in the US Democratic party, operating on the belief that what Rees describes as the current “extreme times”.

She argues that issues such as the battle for universal healthcare, climate change and the rise of the far right demand a vigorous international response: “We need to fight the closed culture that is leading to fascism in different parts of the world”.

They also want to foster a continuous climate of campaigning in the belief it is activism that helps bring new people into politics, and that elections in their four- or five-year cycles come around too infrequently.

Rees cites Alexandria Ocasio-Cortez, the 29-year-old member of the US House of Representatives who once volunteered for Sanders, as an example of the kind of candidate they hope will emerge in the UK, although despite recent changes Labour rules for parliamentary candidates still heavily favour incumbents.

Kelly Coogan-Gehr, the assistant director of public and community advocacy at National Nurses United, agrees that there are “striking parallels” in political developments on both sides of the Atlantic, with both Labour and the Democratic party in transition.

“The US is learning from the Brits that candidates who stand for big, bold, authentically transformative policies – policies with vision – move hundreds of thousands of people to action in a relatively short period of time,” Coogan-Gehr said.

The belief is that Medicare for All represents the kind of popular, transformative policy that is required to defeat Donald Trump, and that its adoption by a Democratic candidate against him would provided a significant base of support.

The Democratic party was in a process of “vital regeneration” as “the American people vote out its extreme centre”, Coogan-Gehr added, while Corbyn’s leadership demonstrated “the potential power that can be harnessed when political parties and movements work together”.