May asked Britain's Queen Elizabeth for permission to form a new government on Friday after an election debacle that saw her Conservative Party lose its parliamentary majority days before talks on Britain's EU departure are due to begin.
On the doorstep of her official Downing Street residence, May said she could rely in parliament on the support of her "friends" in Northern Ireland's Democratic Unionist Party after her governing Conservatives failed to win a majority.
"We will continue to work with our friends and allies in the Democratic Unionist Party in particular," she said.
"Our two parties have enjoyed a strong relationship over many years and this gives me the confidence to believe that we will be able to work together in the interests of the whole United Kingdom."
The DUP - which staunchly defends Northern Ireland remaining part of the United Kingdom, and takes a conservative approach to social issues - increased its number of seats to 10 in Thursday's election.
"We will fulfil the promise of Brexit together and over the next five years build a country in which no one, and no community, is left behind," May said.
"This will allow us to come together as a country and channel our energies towards a successful Brexit deal that works for everyone in this country, securing a new partnership with the EU which guarantees our long term prosperity."
The DUP said earlier on Friday it would not comment on reports that it had agreed to back May's ruling Conservatives/
Some political analysts doubt a Conservative minority government with support from the DUP would last over the long term, and think a second election is likely.
(Reporting by Kate Holton and David Milliken; Writing by Elizabeth Piper; Editing by William Schomberg)
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)