The intervention of former Donald Trump adviser Steve Bannon in European politics could help rightwing parties become the biggest bloc in the European parliament next year, according to Nigel Farage.

The former Ukip leader predicted sweeping advances for anti-EU parties during next May’s European elections, aided by the new project announced by Bannon . Bannon, one of the architects of Donald Trump’s US election triumph in 2016 and the former head of the rightwing Breitbart News, aims to establish a pan-European populist foundation .

Farage told the Observer that, Eurosceptics could become the largest political grouping on the continent and predicted that anti-EU MEPs could secure between 176 and 235 seats in the European parliament elections next May. “My view is that somewhere between a quarter and a third of seats in the European parliament are going to be Eurosceptic and Euro-critical,” he said.

“You could – and it might not happen for all sorts of cultural and left/right political reasons – have a Euro-critical group that is the second biggest in parliament. With a bit of luck and a following wind it could even be the biggest,” Farage added.

Bannon’s foundation, called The Movement, will be based in Brussels and dedicated to campaigning aggressively for a large, anti-EU faction in the European elections next spring. Bannon said last week he had already started raising funds amid speculation that former English Defence League founder Tommy Robinson, currently in jail, might be offered a leading role in its UK wing.

Robinson, whose imprisonment has made him a cause célèbre among the international far-right, could be released this week following his appeal against a 13-month sentence for contempt of court in May.

Farage also revealed that Bannon wanted to offer a rightwing antidote to the centre-right European People’s party (EPP), currently the largest party in the European parliament, and the European Socialists (PES), a social-democratic political grouping that includes the British Labour party, the Italian Democratic party and French Socialist party.

“You’ve got two groups across Europe who are very highly co-ordinated at what they do at elections. This is an attempt to get Eurosceptics to do the same thing,” said Farage.

He added: “The mood for change is very strong. Even though Britain is floundering with Brexit, across the rest of Europe, the Eurosceptics are on the march. Euro-critical and Eurosceptic movements are advancing at a very rapid pace everywhere.”

It has since been claimed that Bannon is also forging links with leading Brexiters, including Boris Johnson, who resigned as foreign secretary this month, environment secretary Michael Gove and Jacob Rees-Mogg, leader of the European Research Group, the hard Brexit wing of the Conservative party. All three are potential rivals to the prime minister and Bannon believes all of them could help deliver his ambition to undermine and eventually paralyse the EU.

However Robert Ford, professor of political science at the University of Manchester and co-author of Revolt on the Right: Explaining Support for the Radical Right in Britain, was unconvinced that Bannon could dramatically shape Europe’s political landscape.

“I think shares in Bannon are overvalued. This idea that he’s going to become this pan-national Dr Evil figure producing this big radical right alignment ... there are some big barriers to entry. Influence in the US doesn’t really translate to influence in Europe.”

A survey of national opinion polls released by Reuters found that Eurosceptic parties could expand their strength in the European parliament by more than 60% at next May’s elections. It predicted that numbers of Eurosceptic MEPs after next May’s elections would rise to 122 of the 705 available seats.