BBC News presenter Martine Croxall was taken off air following a breach of impartiality during Sunday night's edition of The Papers.
The BBC has now ruled that 'several remarks and reactions' made by the presenter caused a 'significant risk' that the audience could believe 'opinions were being expressed' on the Conservative leadership contest.
During her introduction to the programme, which started at 10.30pm on Sunday around 90 minutes after Boris Johnson pulled out of the Tory leadership race, Croxall said: "Well this is all very exciting isn't it?"
"Am I allowed to be this gleeful? Well I am," she told viewers.
Martine, 53, was subsequently taken off air following the episode amid claims she showed bias after Johnson pulled out of the leadership contest.
In her first question to her guests she also remarked: "Can we even show you the front pages just yet, have they arrived? No they haven't arrived. It's all a little bit, you know, lastminute.com isn't it? Because all the front pages were probably out of date by the time we received them."
After reviewing hundreds of viewer complaints, the BBC has issued a statement which reads: "In this programme several remarks and reactions from the presenter caused a significant risk that the audience could believe opinions were being expressed on the Conservative leadership contest.
"In addition, there was insufficient counter and challenge to some of the opinions expressed by guests on the programme.
"Taken together, this meant that this edition of The Papers did not meet our editorial standards, as it gave the audience the opportunity to infer an editorial position on the part of the BBC.
"This does not accord with the BBC's commitment to editorial impartiality."
Martine Croxall will also potentially be barred from presenting The Papers for the foreseeable future.
The BBC's statement comes after some viewers, including several Tory MPs reacting to a clip on social media, complained it displayed bias.
Following Martine's comments on The Papers, many viewers took to social media to share their frustration – with some calling for an Ofcom investigation.
"Martine Croxall of BBC News shows her bias when surely a newsreader should be impartial. Unfit for the job," said one angry viewer.
A second tweeted: "Martine Croxall is rightly being pilloried for this partisan display of giddy excitement as News broke of Boris Johnson dropping out of the Leadership contest. This lapse of impartiality and professionalism illustrates why so many accuse the BBC of bias."
While a third added: "Ofcom are going to be busy after Martine's comments, for sure."
Following the programme, a statement from the broadcaster said: "BBC News is urgently reviewing last night's edition of The Papers on the News Channel for a potential breach of impartiality.
"It is imperative that we maintain the highest editorial standards. We have processes in place to uphold our standards, and these processes have been activated."
As a rule, the BBC has a strict set of guidelines for employees which prohibits them from expressing any bias, with Section 4.1 of their editorial guidelines stating: "The term 'due' means that the impartiality must be adequate and appropriate to the output, taking account of the subject and nature of the content, the likely audience expectation and any signposting that may influence that expectation."
The Mirror has reached out to a BBC spokesperson for further comment on this story.
