The SDLP has made a renewed call for parties here to "find a way forward through Brexit" together after Friday's historic exit from the European Union.
Nichola Mallon said that while all the parties here differed in their position on Brexit, "all agree that the way in which Northern Ireland is being dragged out of the EU is not acceptable".
During the first main sitting of the restored Assembly last month, all the Stormont parties rejected the Government's EU withdrawal plan without dissent, following a near three-hour debate in the chamber.
The SDLP's Assembly leader urged the parties here to "work collaboratively" as the Brexit process moves forward into the transition period, in which key trading agreements are set to be decided over a period of 11 months.
"We believe Brexit is a socio-economic and political disaster for all people living on these islands," said Ms Mallon.
"There is a responsibility on all parties in the Assembly to resist the opportunity to point-score and instead to show real leadership and maturity.
"While we certainly welcome the fact that there is to be no border on this island, we recognise the serious consequences for our business community if unfettered access is not secured for trade east-west also.
"The possibility of a new cliff edge into a no-deal Brexit at the end of this year still looms.
"New questions remain unanswered on trade and future relationships."