London zoo has been accused of discriminating against its zoo-goers by allowing them to watch the lions in their enclosure.
The zoo said it had “taken all steps necessary to ensure that this was not the case”.
The zoo has “a strong record of supporting the conservation of lions”, according to the BBC.
“We are working closely with local authorities to ensure this does not happen again,” said the zoo in a statement.
“The lion population at London Zoo is one of the highest in the world and the zoo has a strong record on this.”
It added: “This is a difficult situation for us and we are taking all steps possible to ensure the safety and wellbeing of our visitors and staff.”
The BBC reported that zoo officials were “struggling to understand why they had allowed the visitors to watch, or even seen the lions”.
The BBC also reported that zookeepers were “pushing for more staff to work at the zoo”, with the London zoo already facing a public backlash after its lions were put down.
It added that the zoo was “aware of the allegations”.
“The London Zoo has always been a place where people come for the camaraderie and the wildlife, and that has not changed,” the zoo said in a separate statement.
In December, a judge in California ordered the zoo to pay $13 million (£9 million) to the families of three young lions killed in captivity.
The animals were found dead in their enclosures in the California city of Merced.
The lions were killed by a “sneaky” keeper who used a tranquilizer dart in the hope of calming the lions, according to a statement from the zoo.
The ruling was upheld by a California appeals court.
London’s zoo said the lions had died because they “took too long to recover”.
It added it was working with law enforcement to “find out exactly what happened and make sure it never happens again”.