A baby girl died after her "cruel and arrogant" parents went on the run and lived "off grid" in a tent, a court has heard.

After the baby died, Constance Marten, 36, and Mark Gordon, 49, left her in a disused shed inside a shopping bag covered in rubbish "as if she was refuse", the Old Bailey was told.

Constance Marten's family were the previous owners of Crichel Estate in Dorset, and her father, Napier Marten, was a page to Queen Elizabeth.

Jurors heard that the infant was the couple's fifth baby, their other children having previously been taken into care.

It was their "selfish desire" to keep the baby that ultimately led to her "entirely avoidable" death, prosecutor Tom Little KC said on Thursday.

Opening their trial, Mr Little said the baby "would still be alive if it was not for the reckless, utterly selfish, callous, cruel, arrogant and ultimately grossly negligent conduct of the two defendants on trial".

He told jurors: "They put their relationship and their view of life before the life of a little baby girl."

Mr Little said the defendants decided they "knew best" and ignored the advice they were given rather than act in the vulnerable baby's best interests.

"They decided that, in the middle of a cold winter and in cruel and obviously dangerous weather conditions, they would deprive the baby of what it needed - warmth, shelter and food and ultimately safety," he said.

"They essentially went off-grid and lived in a tent with hardly any clothes, no means of keeping and remaining warm and dry, and with scarcely any food.

"Their selfish desire to keep their baby girl led inexorably to the death of that very baby.

"They went, and remained, on the run. Giving birth to the baby on the run. Not seeking any medical assistance before, during or after birth. Not registering the birth but moving from location to location.

"When the hunt by the authorities to find them, which became national front page news almost exactly a year ago, intensified, so their desperate selfishness increased and so did the risks and the dangers to the baby. "

The couple began camping in "freezing and obviously dangerous conditions" on the South Downs with insufficient clothes, equipment and food and no medical assistance, the court was told.

Mr Little said: "That baby never stood a chance. After the baby had died, the defendants did not hand themselves in but instead remained off-grid and trying to hide, leaving the body of their dead baby in a shopping bag covered in rubbish, as if she was refuse, and left in a disused unlocked shed."

The couple, of no fixed address, deny manslaughter by gross negligence of the girl between January 4 and February 27 last year.

They are also charged with perverting the course of justice, concealing the birth of a child, child cruelty, and causing or allowing the death of a child.

The trial before Judge Mark Lucraft KC is expected to go on until March 8.