Donald Trump praised the role of faith in inspiring the nation's commitment to charity and liberty during an address observing the annual National Day of Prayer.
Speaking before reporters and religious leaders in the landmark's Rose Garden, he said: "We are proud of our religious heritage.
"And as President, I will always protect religious liberty. We've been doing it..."
The US leader also signed an executive order he said would guarantee "equal access" to federal government funding for religious groups
The 71-year-old said the new measure would also grant religiously-affiliated groups "equal right to exercise their deeply held beliefs".
He explained: "The faith initiative will help design new policies that recognise the vital role of faith in our families, our communities, and our great country.
"This office will also help ensure that faith-based organizations have equal access to government funding and the equal right to exercise their deeply held beliefs.
"We take this step because we know that, in solving the many, many problems and our great challenges, faith is more powerful than government, and nothing is more powerful than God."
He was joined on the grounds of the White House by Cissie Graham - the granddaughter of Billy Graham, US Catholic leader Cardinal Wuerl and the Muslim US Army chaplain Dawud Agbere.
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