"Critical and immediate challenges concerning the economy, health, and education are best addressed through the collective efforts of a devolved government chosen by, and accountable to, its people.
"The United States enjoys a deep and long-standing relationship with Northern Ireland, grounded in ties of kinship, culture, commerce, and shared values.
"We remain deeply committed to preserving the peace dividend of the Belfast/Good Friday Agreement and will always strive to protect these gains for all communities.
"We look forward to continuing our work with democratic partners in Northern Ireland, and with the governments of the United Kingdom and Ireland, to support peace, prosperity, and stability across the region."
The Taoiseach said: "It is now incumbent on all political parties and elected representatives to deliver on their mandate, through the nomination of a first and deputy first minister and the formation of a new Executive to serve the interests of all of the people of Northern Ireland.
"Powersharing and principles of partnership, equality and mutual respect are at the heart of the Good Friday Agreement, through which peace has been secured and progress achieved for almost 25 years.
"A new powersharing Executive is vital for progress and prosperity for all in Northern Ireland.
"As a co-guarantor of the Good Friday Agreement, the Government will continue to work in partnership with the British Government and engage with the leaders of the political parties in Northern Ireland to seek and support the effective operation of all of the political institutions of the agreement."