But it made clear it will pull its support if she persists with the plan it says will split Northern Ireland from the rest of the UK. After Mrs May lost her Commons majority in last year’s snap election, she struck a confidence and supply arrangement with the DUP that its 10 MPs would support her in key votes. But DUP Brexit spokesman Sammy Wilson said the party would never accept the provision to keep the whole UK in the EU customs union if necessary to keep the Irish-Northern Ireland border open – even if it triggered an election that put Jeremy Corbyn in power.
The DUP says the proposed backstop would treat Ulster differently from the mainland, put up trade barriers with the rest of the UK and exclude it from new trade deals struck by Great Britain.
It will vote against approving Mrs May’s deal with Brussels on Tuesday unless “the backstop is removed”, Mr Wilson confirmed. If the Withdrawal Agreement is defeated, the DUP would not then support the no confidence vote in the Government that Labour expects to call, as the threat of the backstop would Split…Sammy Wilson have been removed, he told the BBC.
But if Mrs May later returned with the same basic package, he said: “We have the option at some future date to remove our support from the Government. We always have that leverage. We don’t want to use it. We entered a commitment with the Government to ensure they stayed in power during this fixed–term Parliament.
“But the agreement is two-sided. The Government agreed they would deliver Brexit and not have Northern Ireland separated from the rest of the UK.
“We have made it clear we will not connive in the destruction of the UK or damage to our own economy, and this agreement does both.
“If it comes to the point where the Government shows a determination to implement the Withdrawal Agreement with its damaging terms at present, or some future version of it which is still equally damaging, we will not be supporting the Government”.
The party will not be mollified if Mrs May promises Parliament a vote on whether to activate the backstop, he made clear.
Mr Wilson said: “A promise for a Parliamentary lock is something the current government cannot make a promise on, because it can’t bind the hands of future prime ministers or governments.”