Theresa May has told representatives from Northern Ireland’s parties that she will publish full details of any deal agreed with the Democratic Unionist Party (DUP) to support a minority Conservative government.

The prime minister made the commitment during separate meeting at 10 Downing Street with the DUP, Sinn Féin, the SDLP, the Ulster Unionists and Alliance.

“One thing we have made clear to the prime minister is that we are concerned that any deal reached is open and transparent and that everybody gets to see the entire negotiation,” Ulster Unionist leader Robin Swann said.

Talks between the Conservatives and the DUP are reported to be progressing well, although it is likely to be early next week before an agreement is finalised. The government announced on Thursday, however, that the queen’s speech, which outlines its legislative agenda, will go ahead next Wednesday.

“Both parties are committed to strengthening the union, combating terrorism, delivering Brexit and delivering prosperity across the whole country. However, whilst talks are ongoing, it is important the government gets on with its business and we are confident there will be sufficient support across the House for passing the queen’s speech,” a Conservative source said.

Sinn Féin president Gerry Adams told the prime minister that a deal between the Conservatives and the DUP to prop up a minority government could be in violation of the Good Friday Agreement.

“We warned Mrs May that the pact between the Tories and the DUP has the potential to undermine past agreements and the re-establishment of the Executive. Any deal that undermines the Good Friday Agreement will be opposed by Sinn Féin and we would hope the Irish Government, ” he said after the meeting.

He told reporters Sinn Féin would support any additional monies going to the Northern Ireland executive as a result of a deal. However, “a little side bargain to keep Theresa May in power, a temporary little arrangement, won’t have any integrity”.

DUP deputy leader Nigel Dodds said he emphasised to the prime minister that his party stood ready to form a new powersharing executive “without any preconditions or red lines”.

Manifesto proposals

Negotiations between the Conservatives and the DUP are understood to be focused on measures to boost the economy in Northern Ireland, as well as proposals to drop some unpopular Conservative manifesto proposals. Some Conservatives are unhappy about the prospect of a deal with the DUP, partly on account of the party’s social conservatism but also because any extra funds for Northern Ireland will prompt calls for equivalent transfers to other parts of the UK.

Scotland’s first minister Nicola Sturgeon on Thursday condemned what she called a “grubby deal” with the DUP, warning that it could undermine the peace process. SDLP leader Colum Eastwood said that the deal must not give the DUP undue influence over the Conservatives, particularly in the context of talks to restore the Executive in Northern Ireland.

“The prime minister will have to do a lot more, however, to convince us that the DUP tail isn’t wagging the Tory dog. Their influence on the British government is a cause for deep concern that must be addressed to assure the public and political parties of the independence of the talks process. The Irish government will be critical to that and they should reassert their role as co-guarantors of our agreements,” he said.

The British government confirmed on Thursday that formal Brexit negotiations will begin on schedule in Brussels next Monday. The first round of talks, led by Brexit secretary David Davis and EU chief negotiator Michel Barnier are expected to last three days.

The announcement came as Ms May is under pressure to soften her approach to Brexit in the light of last week’s election, with some Conservatives calling for economic concerns to take priority over issues like immigration.

A YouGov poll on Thursday found that the prime minister’s favourability rating has plunged since the election from +10 in April to -34 today. Jeremy Corbyn’s favourability has surged from -42 in April to a neutral rating today.