The Northern Ireland minister Shailesh Vara, has resigned over the Brexit deal.
In a letter to Prime Minister, the MP for North West Cambridgeshire said he "cannot support the Withdrawal Agreement that has been agreed with the European Union".
"The EU Referendum offered a simple choice - to either stay in or leave the EU.
"The result was decisive with the UK public voting to leave and that is what we, their elected representatives, must deliver.
"The Agreement put forward however, does not do that as it leaves the UK in a half-way house with no limit on when we will finally be a sovereign nation.
"We can and must do better than this. The people of the UK deserve better."
This resignation comes after Theresa May spoke to Cabinet ministers on Wednesday, who approved the draft terms of her EU withdrawal.
Mr Vara, who backed remain in the referendum, is the first politician to quit their job over Mrs May's draft proposal.
It's thought his exit could spark a flurry of resignations.
Shailesh Vara has been the Conservative MP for North West Cambridgeshire since 2005.
He had been a minister in the Northern Ireland Office since January 2018. Mr Vara was Vice-Chair of the Conservative Party from 2001 until 2005.