Speaking in the House of Commons this afternoon, Labour MP Mr Benn - who has been an outspoken critic of Brexit and proposed legislation to stop the country crashing out of the EU without a deal - hit out at the Government’s Get Brexit Done campaign and talks with the EU.
He said: “If anybody thinks that Brexit has taken too long to get to this point, it’s worth remembering that even if the Prime Minister does get a deal and it gets approved by the House, it’s going to take a very, very long time as we try and negotiate a new relationship with our biggest, nearest and most important trading partners, when one thinks of the list of things to be discussed.”
He said: “It is a very long list and that’s why I say to the frontbench opposite, the phrase Get Brexit Done is incredibly misleading, because we haven’t even begun to get Brexit done as the years ahead will prove.”
Mr Benn added: “We have to face up to the possibility that all we’ll get out of the summit this week is the EU leaders noting some progress has been made and looking forward to further talks.”
And he said the country was “heading for a further extension anyway”.
Downing Street has said Brexit negotiations remain ongoing after reports suggested Mr Johnson is closing in on a new deal after giving significant ground to the EU over the Irish border.
Mr Benn said Mr Johnson’s new concessions put his deal on par with his predecessors Theresa May, whose customs partnership plan caused Mr Johnson to resign as Foreign Secretary.
He also said MPs were approaching a "moment of truth" on whether to hold a second referendum on the UK's membership of the EU.
"I think there is a growing number of members of the House who have come to the view that the only way in the end to resolve this question and to gain consent on the way in which leaving happens, if that were to take place, is to go back to the British people."
Mr Benn said he believed the Government could shift its position on a referendum.
He added: "Now I know the Government has said that under no circumstances will we agree to a confirmatory referendum.
"But let's be honest, there are lots of other things the Government has said during the course of this Brexit mess that they would never do that they are now doing."
He continued: "That is why the moment of truth is approaching for the House and I believe that we will need to enlist the help of the British people in order to do so.
"Not to get Brexit done but to decide whether to remain or go to ahead, and if so how."
He added: "The question is whether the British people have changed their minds.
"Now, I don't know whether they have. The Prime Minister doesn't know. The House doesn't know. So let's ask the people because they will know."