Liz Truss told the Commons she intends to bring forward the Bill within weeks, in an effort to reduce “unnecessary bureaucracy” and protect the Good Friday Agreement.
Asked about the move on Wednesday, she said it would be “very positive” if the UK and EU could negotiate a solution in parallel to the Bill’s progression through Parliament, and write this into the legislation.
But she said the plans to rewrite parts of the deal to address the “very severe” situation in the region cannot be delayed.
She told Times Radio: “I’m absolutely clear that we can’t delay … delivering a solution in Northern Ireland. The situation is very severe.
“The Executive hasn’t been formed since February. And we’re only going to be able to get it back up and running, to get the Belfast (Good Friday) Agreement working again, by delivering this solution.
“Now, if while we’re putting this legislation through we can get a negotiated solution with the EU, that would be very positive – we’d be able to put that into the legislation.
“But we’re certainly not delaying the legislative process because it is urgent that we deliver for the people of Northern Ireland.”
Ms Truss has insisted the proposals to reform the deal are “consistent with our obligations in international law”.
Asked how certain she is of this point, she said: “We’re very clear that this proposal, this Bill, is in line with international law and we’ll be setting out a statement in due course on that.
“Of course the Government always respects the rule of law.”
The Foreign Secretary stressed the importance of making “sensible, pragmatic changes” to the protocol.
She told Sky News: “The reality is it isn’t working on the ground. It has created political instability in Northern Ireland.
“We haven’t seen the Executive form since February. So we do need to make these changes. And these changes will … make it better for everyone.”
She said she wants the EU to “come to the negotiating table” so a “pragmatic solution” can be agreed together.
“But if that doesn’t happen we do need to move ahead delivering this solution for the people of Northern Ireland,” she said.
The UK is planning unilateral action to introduce separate “green” and “red” lanes for goods travelling between Great Britain and Northern Ireland, drawing a line between those destined to stay within the UK and those heading to the Republic of Ireland and beyond.
There will be no crossover between the channels, it is understood, with goods filtering through one or the other, depending on their intended destination.
This will override the current arrangements, whereby Northern Ireland is effectively kept in the EU’s single market for goods, with a hard border down the Irish Sea.
Shadow chancellor Rachel Reeves accused the EU of being “overzealous” over checks on goods destined to stay within the UK, but said the way to solve the problem is not through “megaphone diplomacy”.
She told Times Radio: “I think the EU are being overzealous in the checks.
“There are goods that are destined for market in Northern Ireland, never going to leave Northern Ireland, never going to get into the single market, which is what the EU say is their worry.
“For those goods that are just moving into Northern Ireland then I just don’t think we need the level of checks the EU are pursuing.
“But the way to resolve this is not through megaphone diplomacy, it’s not unilaterally ripping up the protocol, it’s by working in partnership to resolve these very real issues that do exist.”
On Tuesday, European Commission vice-president Maros Sefcovic criticised the Foreign Secretary’s plan and warned that Brussels could retaliate.
Should the UK proceed with the Bill, the EU will respond with “all measures at its disposal”, he said.
The row over the treaty has created an impasse in efforts to form a devolved government administration in Belfast, with the Democratic Unionist Party (DUP) refusing to join an Executive unless its concerns over the situation are addressed.
DUP leader Sir Jeffrey Donaldson said Tuesday’s move was “welcome if overdue”, and a “significant” step towards getting power-sharing in Northern Ireland back up and running.
He told the Commons his party will take a “graduated and cautious approach” as the legislation progresses.
More details about the UK’s plans are expected to be set out in the coming weeks.