A total of 211 MPs have signed a letter calling on the Prime Minister to rule out a no-deal Brexit.
The letter was organised by Conservative MP Dame Caroline Spelman and Labour MP Jack Dromey, who have been meeting weekly since September to discuss their concerns about how a no-deal Brexit could impact the manufacturing industry.
A group of cross-party politicians have now signed the letter, including members of the Liberal Democrats, the SNP and Plaid Cymru.
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"There is a lot of momentum behind this letter, and I think it's important to stress it is signed by MPs in all parties, from all parts of the UK," Ms Spelman told talkRADIO's Julia Hartley-Brewer.
"For the EU we are a very small part of their export market so we're not in a strong position. It would be punitive for us, and it would costs jobs and livelihoods."
'I respect completely the outcome of the referendum'
Dame Caroline Spelman. Image: Getty
The signatories have reportedly been invited by Ms May to meet with her in Downing Street on Tuesday.
"I respect completely the outcome of the referendum and I'm doing my very best to make sure we deliver what people wanted, but I'm trying to do it with other MPs to make sure we do it without costing jobs and livelihood unnecessarily," Ms Spelman said.
"What has united the MPs that have signed this letter, from all parties, all parts of the UK, some Brexiteers, some remainers, is that we do not want to crash out without a deal."