An aristocrat and her partner accused of the manslaughter of their baby have denied the charges they face.

Constance Marten and Mark Gordon pleaded not guilty to five counts relating to their daughter Victoria during a hearing at the Old Bailey earlier today.

Gordon said “not guilty” in a clear, loud voice when answering the charges, with Marten also pleading "definitely not guilty".

Both are charged with manslaughter by gross negligence of the girl, referred to in the charges as Baby A, between January 4 and February 27 this year.

They also face charges of perverting the course of justice by concealing the body, concealing the birth of a child, child cruelty and allowing the death of a child.

READ MORE: New charges filed against couple after baby daughter found dead in allotment

Marten, 36, and Gordon, 49, of no fixed address, appeared before Judge Mark Lucraft KC, who at one point asked the defendants to stop talking to each other while the hearing was in progress.

Gordon wore a grey sweatshirt and bottoms and a green beanie-type hat during the 30-minute hearing.

Marten appeared in the dock in a white blouse and black trousers with her long hair down.

A trial has been set for January 2, with a further pre-trial hearing listed for December 8.

Police found remains at an allotment in Hollingbury, Brighton, in March after a major search over several days.

Marten and Gordon were reported missing on January 5 when their car was found abandoned and on fire next to the M61 in Bolton. Marten had given birth to her daughter days earlier.

The couple, who had been in a relationship since 2015, travelled by taxi to Liverpool, Harwich in Essex, London and finally Brighton on January 8.

Marten’s parents made public pleas for her to get in touch, while police offered a £10,000 reward for information.

After the couple were found in Hollingbury without their baby on February 27, they were arrested and a huge search involving over 200 officers, helicopters, drones and sniffer dogs took place to find the child.

The baby’s remains were found almost two days after the search began on March 1, wrapped in a plastic bag and hidden inside a shed in an allotment in Hollingbury. Detectives believe the baby had been dead for several weeks.

A candlelight vigil was held the following day as residents laid flowers to pay their respects to the baby.