Cabinet Office minister Michael Gove has said the Government will be publishing a framework document setting out its plans to ensure unfettered access for goods from Northern Ireland into the rest of the UK.
On Monday the Government denied misleading politicians here over customs checks post-Brexit. Northern Ireland spokesman Lord Younger said there would be "unfettered access" for local businesses to the UK market.
But he also acknowledged "there will need to be light-touch checks" for "live animal checks and agrifoods, building on what already happens at Larne and Belfast".
Former Ulster Unionist leader Lord Empey told the Lords that ministers had repeatedly assured Parliament that no checks would take place on goods moving to or from Northern Ireland after transition. "There is a widespread feeling that members have been consistently misled," he added.
And Labour former Secretary of State Lord Reid warned that a "clear breach of a vow given by ministers" undermined trust in the Government.
Yesterday Shadow Cabinet Office minister Rachel Reeves told the Commons: "Peace in Northern Ireland was hard-won, we must not jeopardise it. In January the Prime Minister guaranteed unfettered access for goods moving between Britain and Northern Ireland.
"Last week it was revealed that the Government would implement checks on some products crossing the Irish Sea and that there would be new infrastructure at ports coming from mainland Britain to Northern Ireland.
"So can (Mr Gove) confirm whether these additional checks are being planned for when the road map for implementing the protocol will be published?"
Mr Gove responded: "Peace in Northern Ireland, she's absolutely right, is critical and we will shortly be publishing a framework document on how we intend to implement the protocol in order to ensure that we have unfettered access for goods from Northern Ireland into Great Britain and we preserve the gains from the peace process."
Conservative MP and former Secretary of State Theresa Villiers said the customs compliance obligations under the protocol can be implemented without new physical inspections or infrastructure at ports.
She added: "In that case will he intervene with HMRC to stop them making preparations for new physical inspections and infrastructure at Northern Ireland ports?"
Mr Gove replied: "(Ms Villiers) makes a very important point.
"We are one customs territory.
"The protocol makes that clear, and we'll shortly be publishing further details on how we intend to ensure Northern Ireland benefits from that."