Mayor of London, Boris Johnson, has asked London City Councils to “focus on their duties for pest control”.

His call on City Councils comes after Lola and Isabella Koupparis, whose mother hails from Northern Ireland, were mauled by an urban fox who crept into their bedroom.

The nine-month-old twins are continuing to receive treatment at Great Ormond Street Hospital.

Lola suffered facial injuries and both babies had puncture marks and lacerations to their arms. Both have undergone surgery for their injuries.

Johnson said that foxes must be considered a menace due to the fact that in rare circumstances like this they can be a threat to humans. He said “Therefore, it’s right that boroughs should focus on their duties for pest control because as romantic and cuddly as a fox is, it is also a pest.”

The Irish baby girls were found in their crib covered in blood in their home in Hackney. Their parents attempted to scare the animals off the children but they animals seemed unfazed by their presence.

A spokesperson from the Great Ormond Street Hospital said “Great Ormond Street Hospital for Children NHS Trust can confirm that Isabella Koupparis is still a patient at the hospital and continues to receive the highest possible levels of care from medical staff.”

They also confirmed that Lola remained in a serious but stable condition.

The twin’s mother Pauline said that situation was like a “living nightmare”. She also fears that the attack will have a “life-changing effect” on her babies.

The fox is thought to have crept through the patio door on the ground floor which was left open because of the warm weather. Their parents were unaware of what was happening as they watched television in a downstairs room.

The fox then crept upstairs to the twin’s rooms. Their four-year-old brother who was also sleeping upstairs was unharmed.

Lola had facial injuries and some puncture marks on her arm, while Isabella suffered injuries to her arm and both children underwent surgery, she said.

Pest controllers set traps in the area after the attack. A fox was found in one of the traps in the families back garden on Monday night. It was subsequently humanely destroyed.