The vice president of Sinn Féin has called on the Government to assert its role as a co-guarantor of the Good Friday Agreement in order to restore power-sharing at Stormont.
Michelle O'Neill was speaking after a meeting with Tánaiste Simon Coveney in Dublin.
She also said the Government should "address directly the core problem of the denial of rights."
Power-sharing collapsed early last year in a row over the DUP's handling of a botched green energy scheme and a dispute over an Irish language act.
"The Irish Government would not tolerate discrimination against citizens in the 26 counties. The British government would not tolerate the denial of these rights in Britain," Ms O'Neill said.
"I made it clear that discrimination should not be tolerated in Belfast either."
Ms O'Neill described the current relationship between the DUP and the British government as toxic and said she believed the British government's plan was to prevent the restoration of the executive.
"We have been fairly firm in the belief that all along their plan was to do nothing and now I am even more concerned because I believe their plan is to prevent the restoration of the Executive," she said.
Before the meeting Ms O'Neill called on the Taoiseach to deliver on his words when he said the people of the North will never be left behind again.
Meanwhile the DUP leader has said the British government must not "subcontract" its role in restoring power-sharing.
Arlene Foster said there was a part for independent mediation in helping break the 20-month impasse at Stormont.
She met British Prime Minister Theresa May in London as Westminster explores convening fresh political talks.
Mrs Foster said: "We believe there's a role for facilitation but we also believe the British must not subcontract their role, because of course under the Belfast Agreement, until the people of Northern Ireland decided otherwise, the United Kingdom government is in charge of Northern Ireland."
She held a "detailed" meeting with Mrs May about decision-making in Northern Ireland in the absence of a ministerial Executive in Belfast following serious disagreements between former coalition partners the DUP and Sinn Féin.
Northern Ireland Secretary Karen Bradley met the five main Stormont parties this week as she contemplates another push for agreement and is seeking their views about external facilitation.
Sinn Fén has been intensely critical of the British government.
Independent mediators helped previous rounds of political progress in Northern Ireland, including brokering the Good Friday Agreement 20 years ago.
Mrs Foster said civil service decision-making should be quickly rolled out amid the political paralysis.
"There is a whole range of decisions that need to be taken in Northern Ireland very, very urgently and we want to see that happening quickly."
Asked about talks, Mrs Foster said the "first thing we have to get set in motion" was putting in place decision-making.
Mrs Bradley is planning to cut Assembly members' pay and will bring forward legislation giving greater clarity around civil servants' powers to make decisions in the absence of a functioning Executive.
Additional reporting: PA
