Saying she was "very confident that the new director general understands the seriousness” of the issues, Nandy added: "The BBC is one of the most trusted sources of news in the world… it is more important now than ever.
Lisa Nandy at JW3[Missing Credit]
"But that means that where there are mistakes made, where there is bias, that has to be dealt with and acknowledged quickly.
"The problems that have emerged at BBC Arabic, or the issues about the Gaza documentary or at Glastonbury, the BBC in the past has been too slow to understand and acknowledge that.
"I'm confident though, that at the most senior levels of the BBC, that is now understood and that action is being taken to turn that around."
Asked whether she believed the BBC's new leadership would be "strong enough on BBC Arabic", Nandy replied: "I discussed it with the incoming director general."
Brittin, a former Google executive, took the helm of the corporation last month after Tim Davie resigned following the leaked Michael Prescott report, which identified serious editorial and impartiality failings across the BBC.
The report devoted its longest section to the BBC’s alleged anti-Israel bias, highlighting stark differences in coverage between the broadcaster's English and Arabic-language services.
The JC previously revealed that a BBC Arabic reporter, Sally Nabil, who had liked social media posts appearing to justify the October 7 attacks, travelled to the United States to cover a meeting between Benjamin Netanyahu and President Donald Trump.
Last year, the BBC was forced to withdraw a Gaza documentary after it emerged that it featured the son of a Hamas minister without disclosing the connection.
At the time, Nandy said in Parliament that she had discussed editorial standards with then director general Tim Davie “in order to seek urgent answers about the checks and due diligence that should have been carried out ahead of the screening of a recent documentary on Gaza."
The Wigan MP sought "cast-iron assurances" that no money paid by the BBC for the documentary had fallen into the hands of Hamas.
Nandy's latest intervention comes as the BBC announced 550 job cuts, removing almost one in 10 staff to make £500m saving.
It also comes amid scrutiny of the complaints process governing BBC Arabic, part of the World Service, which is regulated by the BBC's own Editorial Complaints Unit and not by Ofcom.
Asked whether that system was effective, Nandy said she had to "tread a little carefully” because “it is not for the culture secretary to tell the BBC how it manages itself and upholds its standards."
However, she said "It is right and proper" that when standards are not upheld, "when the country and Parliament is not able to trust what they see or hear on the BBC, it is important that the BBC accounts for itself and is able to take action to correct that.
"Over the last few years, you've seen on a few occasions where I and the government have been proactive in saying to the BBC, we need to see stronger processes and stronger standards in place.
"Ofcom has a role in that, but ultimately it's for the BBC to make sure that they've got those proper standards in place."
Nandy welcomed the appointment of a deputy director general with responsibility for editorial standards.
"That is something that is long overdue and is a really welcome step forward.
"Ultimately, Parliament is there in order to hold the BBC to account to make sure that it gets this right.
"The BBC is one of the most trusted sources of news in the UK and around the world, and they report without fear or favour, including on the government, as it should be.
"That's why it matters so much that we will always, as a government, work with them constructively to make sure that people from every community, including the Jewish community, especially now, can have confidence in what they see reported."
