ONE of the North-East’s most famous families is locked in a legal fight over a £12m inheritance.

Edward ‘Ned’ Lambton, the seventh Earl of Durham, was left the entire estate of his father, the former Conservative minister Anthony Lambton, who died in Italy in 2006.

As the only son he was willed the fortune rather than his four siblings under the British tradition of primogeniture.

But despite this, three of his sisters, author and TV presenter Laduy Lucinda Lambton, 70, Lady Beatrix Neville, 63, and actress Lady Anne Lambton, 58 , have been trying to acquire a share of their father’s estate.

They believe they could be entitled to shares under Italian law as their father lived there for 30 years after being forced to resign in 1973 after being caught with a prostitute.

Edward Lambton has issued a High Court action aimed at preventing them from using foreign statutes.

He had been negotiating to give his sisters a £1m share in return for them dropping their claims.

The High Court writ details how Lord Lambton made a will in 2004 leaving his estate to his only son.

It says none of the sisters was mentioned in the will and none of them had challenged the will.

The sisters began legal proceedings in September 2011 claiming that under Italian law all Lord Lambton’s assets should be divided.

The seventh earl, whose previous wives include the current spouses of musician Jools Holland and actor Dominic West, is asking the High Court to declare that assets disposed prior to his father’s death do not form any part of his estate.

These are thought to include Lambton Castle at Chester-le-Street, thought to be held in trust.

Ludovic de Walden, lawyers for the sisters, said they were “surprised” by their brother's move, which “seems to have closed the door on what could have otherwise been a private and easily resolved family dispute”.

A spokesman for Lord Durham’s lawyers, Withers LLP, said: “Lord Lambton left everything at his death in 2006 to his only son Lord Durham, having already provided for his other children.”