Sinn Féin has called on the Government to “get real” with the DUP.
Party leader Mary Lou McDonald and MLA Conor Murphy met with Secretary of State Julian Smith in Dublin on Monday.
Mr Smith had visited the city for meetings with political figures on issues around Brexit and the power-sharing impasse at Stormont.
Ms McDonald claimed the confidence and supply arrangement has hindered the Conservatives’ ability to negotiate neutrally with the DUP.
She said the Conservatives instead seek to "placate" the DUP because of their influence in Westminster, rather than hold meaningful talks on restoring local government.
Ms McDonald said: "Julian Smith says the Prime Minister wants to have power-sharing restored, and if that's the case then they need to get cracking and need to get real.
"They say that it (restoring powersharing) is priority, but you would imagine if something is a priority they would move heaven and earth to make it happen, and we're certainly not convinced that the British Government have carried the load or used their influence with the DUP to ensure that solutions are delivered. This is the frustrating thing."
Northern Ireland's power-sharing institutions collapsed in 2017 amid a stand-off between Sinn Féin and the DUP.
"We still are in a situation where the DUP are not demonstrating the necessary appetite to embrace solutions to issues to get the Assembly back up and running, and neither are the British Government in terms of restoring power-sharing or indeed agreeing or embracing the backstop to protect the island of Ireland," Mary Lou McDonald continued.
"Not being unkind to the man (Mr Smith) - the reality is that any British secretary of state or Tory coming here... they don't have the same skin in the game in terms of Irish interests that other people who have been elected here have."