Nigel Dodds, deputy leader of the Democratic Unionist Party, said on Friday that "substance, not timing, will influence" his party's decisions on the upcoming vote on Brexit.
The leader added that his party had held "a long series of discussions" with cabinet ministers and had a "constructive dialogue" with UK officials, but stated that the backstop remained a key problem in Brexit negotiations.
Mr. Dodds added that focus has always been on how Northern Ireland can leave the European Union with the UK, but a lot will depend on "what the government can do to provide guarantees".
The DUP leader added that it was "incumbent" for London, Belfast, and EU leaders to secure a Brexit deal, it would like more progress on the Irish backstop.
Mr. Dodds also said that he would keep in touch with the UK government via phone and will return to London for talks on Monday.
The news comes after UK prime minister Theresa May held emergency talks with the Democratic Unionist Party (DUP) on Friday in order to save her beleaguered Brexit deal before a third Commons vote on the package takes place next Tuesday.
The UK Prime Minister had inked a fragile alliance in 2018 with the DUP after paying £1bn in taxpayer's money.
— Andrew Pierce (@toryboypierce) 15 March 2019
— Alan Haworth (@haworth_haworth) 14 March 2019
MPs voted 413 to 202 in favour of extending Article 50 up to 30 June, on the condition that Commons backs the Prime Minister's deal by next Wednesday. But EU leaders may delay the UK's Brexit date indefinitely if British MPs fail to cement a deal before then.
European Council president Donald Tusk said on Thursday that EU leaders may opt for a long extension should the UK find it "necessary to rethink its Brexit strategy".
— Donald Tusk (@eucopresident) 14 March 2019
DUP leader Arlene Foster is also holding talks on Thursday with US president Donald Trump and vice president Mike Pence in Capital Hill, in order to negotiate protections for the Irish backstop whilst praising the "great commitment amongst the US administration to help Northern Ireland".
— Arlene Foster (@DUPleader) 14 March 2019
Mrs. May's Brexit deal suffered a major defeat 242 to 391 in Commons on Thursday, with a margin of 149 votes, but rejected leaving the EU without a deal "under any circumstances" on Wednesday. But all voting sessions are non-binding, meaning that London could still withdraw from the EU without a deal by the 29 March deadline.