A millionaire antiques dealer has today claimed 'diminished responsibility' as he admitted strangling his seven-year-old daughter to death at his £1million London home - but has denied murder.

Robert Peters, a Chinese porcelain expert, wrapped a dressing gown cord around little Sophia's neck on November 3 last year, then phoned police to confess what he'd done.

After police arrived at the detached Raynes Park property he shared with Sophia's Thai mother Kittiya Promsat, Peters was arrested and initially charged with attempted murder as medics battled to save his daughter's life in hospital.

But the charge was upgraded to murder the following day after she died in hospital.

At a plea hearing today at the Old Bailey the 55-year-old pleaded guilty to Sophia's manslaughter on the grounds of diminished responsibility, but that was rejected by the prosecutors who will press ahead with a murder trial due to start in April.

Little Sophia died after she was found seriously injured at her home in south-west London. She is pictured online holding a sign saying 'I love you mum and dad'

Robert Peters, 55, throttled daughter Sophia at the house in Wimbledon on November 3 last year, leaving her lying severely injured on a bedroom floor. She was rushed to hospital but died the following day

Wealthy antiques dealer Robert Peters (pictured) has admitted at the Old Bailey that he strangled his seven-year-old daughter Sophia at his home in Wimbledon

Peters had recently moved to the home with Sophia's Thai mother Kittiya (pictured together)

Peters today appeared before Judge Nicholas Hilliard QC for a plea hearing at the Old Bailey.

The antiques trader spoke only to identify himself and showed no emotion during the brief hearing.

Peters, who appeared in the dock wearing a grey prison issue tracksuit, denied murder but pleaded guilty to Sophia's manslaughter by reason of diminished responsibility.

Prosecutor Deanna Heer said the plea was not accepted and there will be a trial at the Old Bailey from April 23.

The trial is expected to go on for up to two weeks. A further case management hearing was set for March 28. The defendant was remanded into custody.

Robert Peters, 55, allegedly attacked Sophia while they were alone at the £1 million family home in Wimbledon, south-west London, (pictured), where a £50,000 Jaguar XK convertible was parked on the driveway

Peters, who has been married three times, is a specialist in porcelain and runs a business with his twin brother, Richard, in Kensington Church Street.

The business is in an antiques arcade with about a dozen other traders.

Companies House accounts reveal that Peters had business assets worth a further £1.3m in 2016.

Peters, 55, is accused of attacking Sophia at their home in Raynes Park, south-west London, in November

The brothers hit the headlines in 2010 after they bought a Chinese vase with an asking price of £136 for almost £100,000 after a bidding war.

Richard Peters, who reportedly lives in Tel Aviv, said it was a 'bargain' and would likely be sold on to a Chinese client.

A third brother, Paul, is also in the antiques trade in Harrogate, North Yorkshire.

Ex-wife Sara, 57, from Marylebone, central London, said she had not spoken to Peters in 25 years.