The Government said this week it was putting money into planning for a “no deal” scenario if talks fail.
Lord Forsyth said it was essential for the UK to have “a plan B" and mocked the idea of going into Brexit talks without being willing to walk with no deal agreed.
The Tory Lord criticised Labour MP Chi Onwurah for saying the prospect of a “no deal” should “not be an option”.
Speaking on BBC’s Any Questions?, he said: “Those people who say, actually Chi has just said this, that we shouldn’t say that we are prepared to walk away – I would love to do a negotiation with anyone who says they are not prepared to walk away.
Lord Forsyth mocked a Labour MP for suggesting she wouldn't be prepared to walk away from the EU
“We have to have a plan B for the future of our country and for the future of our children.
“Of course we don’t want to walk away but you should learn from your mistakes. David Cameron made the mistake of negotiating with them and saying 'whatever you decide we’ll never want to leave the European Union', and as a result they gave us nothing.
“Which is why we had the referendum and why we voted to leave.”
Speaking on the show, Shadow Minister for Industrial Strategy Chi Onwurah, insisted Labour’s policy was to protect jobs when negotiating Brexit with the European Union.
I would love to do a negotiation with anyone who say’s they are not prepared to walk away
She said: “This is about all our futures and we need a jobs-first Brexit that protects peoples jobs.
“Just to say the idea of no deal is an option on the table when that would mean the border with Northern Ireland, it would mean that 30 to 40 per cent tariffs on dairy, it would mean 10 per cent tariffs on automobile.
“Apparently it would mean aeroplanes could not take off or land either.
“That should not be an option. We have got to be clear we want to protect jobs. Obviously, it is hard negotiations, we need to be strong, we need to be firm, but going win with a shared vision of where you are trying to get to.”
After the fifth round of Brexit negotiations came to a close this week, the EU’s chief Brexit negotiator Mr Barnier also conceded the bloc was preparing for “no deal” if talks fail.
Brexit negotiations: UK’s key policy positions
Wed, September 13, 2017
Here is a summary of the UK’s main proposals for Brexit
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The Frenchman said: “I think there is a real will on the European Union’s side to build a strong and lasting relationship of cooperation with the UK.
“And, the present Government of the United Kingdom has chosen to implement the exit of the UK from the European Union, but also the exit from the single market and the customs union.
“So, when the time comes we will talk about a free trade agreement and we will be ready to do that whilst respecting the full integrity of the single market and the European Union’s decision making autonomy there.
“Slowly but surely, over the next few weeks, I will explore ways of getting out of this deadlock we find ourselves in on the financial issues with a view to making sufficient progress by the next European Council.”
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