Julian Smith has rejected a claim he is using Northern Ireland's health crisis as political leverage to force Stormont's parties back into government.
His comments come a day after an unprecedented strike action across Northern Ireland which saw thousands of nurses take to picket lines in a dispute over pay and pensions.
A last minute appeal from the five main parties, providing "political cover" for pay parity to be restored, failed.
The parties have been engaged in talks aimed at restoring power sharing since Monday. The secretary of state has warned an election could be called if there is not a resolution by January 13.
Mr Smith has held talks with the Treasury in London on the possibility of securing more funding for any restored Executive. The DUP and Sinn Fein have called for an injection of cash.
The Secretary of State refused to be drawn on if a talks breakthrough was expected before Christmas.
Responding to party claims that he could intervene to address striking workers' pay demands, the Northern Ireland Secretary said: "I have explained previously that I don't believe I have the power to intervene under the Good Friday Agreement, under that agreement that has provided stability to Northern Ireland, over the past decades.
"Health was established as a devolved matter.
"And we're prioritising health today in terms of the talks process. And I really, really hope that if we can get the devolved institutions back up and running, that is the most sustainable way to getting pay parity for the trade unions and for the workers that have been going on strike."
Stormont talks were held on Friday to deal exclusively with the health issue.
Mr Smith said he did not want to get into a "blame game" with local politicians over the issue.
"But what I know is I do not have the power to direct the Northern Ireland Civil Service," he added.
"I've been working hard behind the scenes to try to see what money might be available to try to see how we can move this dispute on and my conclusion is, the best way I can help is to get a sustainable deal over a number of years that gives nurses and hospital workers what they want, and ensures that they have security and the best way to do that is that the executive gets up and running as soon as possible to ensure that those workers have stability over Christmas, but over the next two or three years as well."
He denied that his request for the parties to agree a series of commitments to tackle the health crisis was evidence of the Government dictating policy to the devolved parties.
"I'm obviously going to be as activist as I can be in encouraging political leaders to deliver the commitments that I believe are needed," he said.
"That is quite different from me telling the Northern Ireland Civil Service what to do, but I'm going to do everything I can to deliver for nurses, to deliver for hospital workers by using my influence with party leaders to ensure that they get back in an Executive and that they deliver for people on the front line."
Asked if the Government would offer financial support to help address the problems in health, he said: "I'm expecting there will be a number of requests, financial requests, and I'm already in touch with the Treasury, and the key thing is that party leaders here agree to go back into the Executive.
"The UK Government stands ready to support that decision in any way we can."
Mr Smith would not be drawn on whether there was any likelihood of a breakthrough in the talks to restore power sharing before Christmas.
"These can be very difficult and long processes, we have had some very good engagement this week," he said.
"The most important thing is that people trust each other, and that party leaders who have got different agendas come together in the interests of Northern Ireland. I believe there is a will to do something.
"But let's see how long that takes. It's important, above all, that we have a sustainable Stormont that can last over the next decades and it's that that I want to ensure is delivered through these talks."