Both were close allies of Bruno Mégret, the party's deputy leader. Until recently he was regarded as the natural heir to the party's leader and founder, Jean-Marie Le Pen, but now Mr Mégret is in open conflict with him.

Mr Le Pen, has been isolating Mr Mégret and his supporters after a row over who should lead the party's list at next year's European election.

A BBC correspondent in Paris, Stephen Jessel, says the crisis which has now erupted into open conflict is perhaps the most serious in the party's history.

Le Pen's anger

Mr Le Pen was angered by claims by Mr Mégret that he should lead the Front's list at the elections if Mr Le Pen were legally barred from standing.

Mr Le Pen says France is at risk from tide of immigration

Although Mr Le Pen can now stand himself, he was enraged by what he saw as Mr Mégret's presumption, and since then has been forming alliances within the party to isolate him and reducing his importance.

The two Mégret loyalists dismissed on Saturday were thrown out of a council meeting to discuss policy for the European elections after Mr Le Pen called on "undesirable persons" to leave. Boos and catcalls followed, and that led to proceedings being suspended and an emergency meeting of the party's political bureau being held.

"This is the famous purge we've been waiting for," said Nathalie Debaille, an ally of Mr Mégret and one of the two people expelled. "Anyone who has ever come anywhere near Bruno Mégret will be pushed aside."

Election ambitions

The Front is the only major party in France openly hostile to further European integration and is hoping to win 20% of the vote in next year's elections compared with its usual 15%.

Mr Mégret - the architect of the strategy that has given the Front a foothold in the running of four regional councils - does have his backers within the movement, notably in the Paris area.