The King and his estranged brother Andrew came within half a mile of each other at Sandringham yesterday – though the siblings could not be further apart.

Charles arrived on the Norfolk estate to spend some time at Wood Farm, his father's former home, as the main house is currently open to tourists.

It is just 0.6 miles – a 14-minute drive on the local roads – from his disgraced brother's house, Marsh Farm.

But Charles, 77, will not be visiting Andrew Mountbatten-Windsor this week, and nor has he invited the former royal to see him.

It suggests the monarch remains determined to draw a line in the sand with his brother while police continue to investigate allegations of his misconduct in public office.

His Majesty has already stripped Andrew of all his remaining titles and privileges and engineered his departure from his Royal Lodge mansion to an isolated new home in Norfolk. 

Andrew briefly lived at Wood Farm following his eviction from Windsor's Royal Lodge as he waited for his new home to be adapted to his needs.

Buckingham Palace has made clear that it remains fully supportive of the police investigation and will assist them if requested.

After Andrew's arrest in February, a Palace spokesman said: 'The King has made clear, in words and through unprecedented actions, his profound concern at allegations which continue to come to light in respect of Mr Mountbatten-Windsor's conduct.'

On Friday, it was revealed that Andrew is now being investigated by the police over potential sexual offences in addition to existing enquiries over claims he leaked secrets to paedophile financier Jeffrey Epstein during his decade as the UK's trade envoy.

The King last appeared with his brother in public in September last year at a requiem mass in London for the late Duchess of Kent.