Former Foreign Secretary David Miliband says the British government needs to create a coherent negotiating plan for Brexit before it's too late.
Mr Miliband believes the prospect of a no-deal Brexit could be a catastrophe for the country and is willing Theresa May to avoid it.
Additionally, upon the negotiation of any deal agreed with the EU, Mr Miliband believes the British people should be allowed to vote on whether it is acceptable at a referendum.
"There's a great fear now amongst, surely, every part of the British population that the Government is not in control of its own business, it's not in control of its own party and that we're staring in the face the real economic carnage of a no-deal Brexit," Mr Miliband told ITV News.
"I think it's incredibly important that the Government gets a grip of itself because we've waited far too long for the Government to have a coherent negotiating position of its own."
Mr Miliband says the general public should be allowed to vote again on Brexit once the UK have agreed a final deal with the EU.
"I also think there are very significant stakes for all of us.
"My own view is that is the right way forward is for the Government to conclude its negotiations, but then to ensure that the deal they strike is put to the British people, so that they know what they're voting for and having voted on the principle of Brexit in 2016, they should have the chance, finally, to decide if they want to go ahead with the deal as its details are filled in."
Mr Miliband, who was a Labour MP for 12 years, also distanced himself from joining any breakaway party.
Asked if he would join a new party, Mr Miliband said: "I am not even thinking about that, at the moment, because the country faces a genuinely generational choice about the form of Brexit it choose or whether it goes ahead with Brexit at all.