One of Jeremy Corbyn’s shadow ministers has admitted to organising a campaign to stop a fresh Brexit referendum, despite Labour’s backing for the policy.

Gloria De Piero refused to answer questions about how her campaigning could be squared with her frontbench role as a spokeswoman for justice issues.

Critics said Mr Corbyn’s “complete lack of leadership” on Brexit would be underlined if he allowed shadow ministers to openly oppose party policy to push for a second public vote.

Ms De Piero’s actions were revealed when she joined other Labour referendum opponents in urging fellow MPs to join their cause at a meeting staged in Westminster.

An email sent by the group, seen by The Independent, is entitled “Respect the Result: No Second Referendum” and encourages MPs unable to attend to register their opposition in order to stay “in touch”.

It reads: “We are writing to you as someone who has expressed concerns at the possibility of a second referendum.

Top politicians' Brexit tweets haven't aged well Show all 18 1 /18 Top politicians' Brexit tweets haven't aged well Top politicians' Brexit tweets haven't aged well These billboards were plastered by campaign group Led By Donkeys @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well Undated handout photo issued by Led by Donkeys of their billboard featuring a blank tweet in Jeremy Corbyn's Islington North constituency in protest over what they claim is his lack of leadership on Brexit. PRESS ASSOCIATION Photo. Issue date: Tuesday February 12, 2019. For the past month, campaign group Led by Donkeys has been putting up posters all over the country featuring quotes mostly from hard-Brexit MPs which claimed the process of leaving the EU would be easy. The Labour leader is the group's latest target because of his failure to back a second referendum on Brexit. See PA story PROTEST Donkeys. Photo credit should read: Led by Donkeys /PA Wire NOTE TO EDITORS: This handout photo may only be used in for editorial reporting purposes for the contemporaneous illustration of events, things or the people in the image or facts mentioned in the caption. Reuse of the picture may require further permission from the copyright holder. PA Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter Top politicians' Brexit tweets haven't aged well @ByDonkeys / Twitter

“Labour MPs who are concerned at the implications of Labour, and parliament, voting for a second referendum, are holding a meeting.”

It adds: “If you can attend this meeting, please click YES on the voting button at the top of this email. If you cannot attend, but would like to be kept in touch, please click NO, but keep me in touch.”

The meeting was staged just days before a likely Labour amendment to Theresa May’s second “meaningful vote” on her stalled deal in order to force a referendum, after Mr Corbyn’s U-turn.

John McDonnell, the shadow chancellor, said the party’s MPs would be ordered to back a bid to allow the prime minister’s agreement to pass – but subject to a public vote confirming it.

Several dozen Labour MPs oppose a second referendum, but supporters hope to significantly shrink that number if the vote is whipped.

The Independent is campaigning for a fresh public vote through its Final Say campaign, with more than 1.1 million people having signed our petition.

Chris Leslie, The Independent Group MP who defected from Labour, said: “Those in the Labour party who believe the public should give their consent for this Brexit must ensure Labour’s leadership do everything necessary to deliver that outcome.”

And Vince Cable, the Liberal Democrat leader, said: “There has been a complete lack of leadership from Jeremy Corbyn on this issue.”

The Independent has asked the Labour leader’s office if any action will be taken against Ms De Piero, the MP for Ashfield, in Nottinghamshire, for defying party policy.

The MP declined to discuss her frontbench responsibilities, but told The Independent: “My views on the subject are well known and I talk to colleagues all the time.”

The controversy came as nine Labour MPs used an article in The Independent to urge colleagues to unite around Mr Corbyn’s commitment to another referendum.