The Northern Ireland party whose 10 members of Parliament support British Prime Minister Boris Johnson's government believe a deal can be done in the coming weeks to maintain an open border in Ireland, a senior member said Sunday.

The so-called backstop mechanism to uphold the seamless Irish border after Brexit has proven a key obstacle to agreeing an EU-U.K. divorce deal, which is needed to avoid a disorderly British exit from the European Union on Oct. 31.

"The time between now and October 31 means that the opportunity to find a solution still remains," Democratic Unionist Party chief whip Jeffrey Donaldson wrote in the Sunday Independent, Ireland's best-selling Sunday newspaper.

"The DUP is committed to achieving that deal and the same desire exists within the U.K. government," he said.

Donaldson said, however, there is widespread opposition among pro-British unionists in Northern Ireland to the EU's current "backstop" proposal.

The proposal could keep Northern Ireland effectively inside the EU's customs union and single market, and create barriers for trade with the rest of the United Kingdom.

"We need to agree alternative arrangements to protect cross-border trade and cooperation in the form of practical solutions that do not breach the core principles of the Belfast/Good Friday Agreement," he said, referring to the 1998 peace deal that requires consent between pro-British unionist community and Irish nationalists.

Donaldson said no unionist members of the Northern Ireland assembly support the backstop, and the "hard political reality" is that "anything not commanding cross-community support is doomed to failure."