What is the 'Irish backstop' and will Theresa May's government survive to cut a Brexit deal?

Theresa May’s pledge to keep Britain in the European Union’s customs union – even if only temporary – has again raised the prospect of an Irish ‘backstop’ solution to the Brexit impasse.

The Prime Minister’s explosive decision, which raises the prospect of Cabinet resignations including from Tory Commons leader Andrea Leadsom, would avoid the need for the reintroduction of a hard border between the UK and the Republic, and a no-deal Brexit

But the proposal has many opponents before it gets approved.

Despite Mrs May’s decision, it is highly unlikely that will be the end of arguments, so why is the Irish border issue proving so contentious?

What is the Irish ‘backstop’?

The backstop would keep an open border on the island of Ireland when Britain leaves the EU next year.

There is no hard border at present, as goods and services are traded between the two countries with few restrictions as both are currently part of the EU single market and customs union.

However, once the UK leaves Brussels that could all change, depending on what deal is brokered.

Under Mrs May’s latest announcement, the need for a hard border in Ireland would be parked as Britain would remain in the customs union for a limited time only – although the government has not said how long this will be.

What does the EU think?

Brussels wants a backstop that would mean Northern Ireland remaining in the customs union as well as large parts of the single market.

However, the EU wants this deal to apply only to Northern Ireland, which is unacceptable for many in the Tory party as well as the Democratic Unionist Party, which helps prop up Mrs May’s government.

What do hard Brexiteers think?

Hard Brexiteers want the UK to leave the union and the single market when Britain exits the EU but that is not their only concern with the backstop.

There are fears among some that any backstop which applies to only to Northern Ireland, would mean the border is essentially drawn down the middle of the Irish Sea.

And if there is any separate status for Northern Ireland from the rest of the UK, it is seen as potentially damaging to the union as a whole.

So what is actually likely to happen?

Only one thing is certain – more political turmoil.

This weekend will likely see the latest shots fired as the UK government tries to scramble towards a deal.

As many as three Cabinet members could resign because of the backstop – Esther McVey and Penny Mordaunt as well as Leadsom – and speculation that disaffected Tories could force their party into another leadership battle, raising the prospect of another general election a no-deal Brexit, and even a second referendum.