The UK government has committed to providing £2 billion to support the new Northern Ireland Executive.
The funding is made up of a £1bn investment guarantee from the UK Government and £1bn new cash.
It is the biggest financial package for Northern Ireland in over a decade.
Julian Smith, Secretary of State for Northern Ireland, said: "This £2bn injection will help transform public services in Northern Ireland, including ending the nurses' pay dispute.
"New Decade, New Approach is about putting Northern Ireland's Assembly on a sustainable footing.
"This funding provides certainty to the Executive and ensures much-needed reforms across health, education and justice can be delivered."
The financial package comes with stringent conditions contained within the New Decade, New Approach deal to deliver a greater level of accountability for public spending and ensure the new Executive is building sustainable public services.
A new UK Government - Northern Ireland Executive joint board will also be established. It will be convened by the Secretary of State for Northern Ireland, to oversee implementation.
There will be a rapid injection of £550 million to put the Executive's finances on a sustainable footing.
This will include £200 million to resolve the nurses' pay dispute immediately and deliver pay parity over the next two years.
The financial support will also be used for public services, infrastructure investment and to address Northern Ireland's 'unique circumstances'.
The deal includes strict financial conditions such as the establishment of a new independent Fiscal Council.
But it does not include any conditions about the raising of revenue by the Executive - that will be a matter for the Executive to decide on if it wants to release extra funds.
However, Stormont Finance Minister Conor Murphy has said he will not accept the £2 billion package from the UK Government.
He said: "The parties restored the Executive in good faith on the basis of the two governments' New Decade, New Approach document. The British Government undertook to provide the additional funding needed to deliver the ambitious commitments in the document.
"My officials are in the process of fully costing what is required but, against the request of the First Minister and Deputy First Minister, the British Government has gone ahead and made this announcement."
Mr Murphy said "£1 billion of this was already coming to the Executive.
"A further £240 million was already promised as part of the Confidence and Supply agreement.
"The bottom line is with this proposed package, our public services face a shortfall of at least £1 billion next year alone.
"This will make it extremely difficult to fund public services."
