Previously the UKIP delegation to the Strasbourg parliament under former leader Nigel Farage had been a member of the populist Europe of Freedom and Direct Democracy group.
But Farage, while still an MEP and chairman of the EFDD, has resigned from UKIP, criticising what he sees as new leader Gerald Batten's association with toxic far-right figures such as anti-immigration activist Tommy Robinson.
And Batten has now joined Le Pen's Europe of Nations and Freedom (ENF) group in the parliament, which also includes members of Austria's Freedom Party, Italy's League, the Netherlands' PVV, Belgium's Vlaams Belang and Poland's KNP.
Le Pen's French party, which makes up about half of the group, celebrated the new arrivals, and the leader herself retweeted a picture of Batten and welcomed him, Stuart Agnew and James Collins on board (see below).
Bienvenue, au sein de notre groupe ENL au Parlement européen, au président du UKIP @GerardBattenMEP, à Stuart Agnew et Jane Collins.
— Marine Le Pen (@MLP_officiel) January 15, 2019
Another British MEP, former UKIP member Janice Atkinson,, was already an ENF member.
Farage remains the most high-profile British eurosceptic in Strasbourg, but his former party has fragmented and lost ground in Britain despite the success of the leave camp in the 2016 Brexit referendum.
If Britain leaves the European Union as planned on March 29, there will be no British members in the next EU parliament, with elections to be held across the continent between May 23 and 26.