Davidson and Mundell 'could resign over Brexit deal' - BBC News
Ruth Davidson and David Mundell will not support any deal that introduces different arrangements for Northern Ireland.
At the beginning of the summer the government's senior ministers held a day-long meeting about Brexit at Chequers, the prime minister's official country home in Buckinghamshire.

The aim was to agree what the government wanted from negotiations with the EU about the future relationship between the UK and the EU over Brexit. The plan that emerged from the meeting has become known as the Chequers plan, or sometimes simply Chequers.

The key aim of the plan is to create a free-trade area for goods moving between the EU and the UK while stopping freedom of movement for people between them.

To do this, the UK would commit to collecting import taxes, known as tariffs, on behalf of the EU for goods that arrive in the UK on their way to the EU. Meanwhile, goods that were staying in the UK could be charged at a different rate, depending on any future trade deals the UK agrees with other countries.

The UK would also agree to a "common rulebook" with the EU for manufactured goods and food, which would mean following EU rules and standards. In the future, if the EU changed any of its standards, the UK could decide not to follow those changes but at the risk of losing the free trade agreement for those goods.

The government believes the combination of the common rulebook and collecting tariffs for the EU would avoid the need for checks on goods passing between the UK and the EU, including over the Irish border.

However, the EU doesn't accept all proposals in the Chequers plan. It thinks the proposals amount to "cherry-picking" parts of EU membership - in other words, keeping the bits the UK wants to stay attached to, while rejecting other rules. The EU is also unconvinced the UK would be able to accurately track all the goods moving through it.