PHILADELPHIA, United States (AFP) — Pope Francis paid tribute Saturday to America’s defence of basic freedoms, especially religious liberty, and urged immigrants not to be discouraged by the “challenges and hardships” they face in the United States.

Francis addressed a crowd of tens of thousands — some waving Vatican flags — gathered outside Independence Hall in Philadelphia, where the Declaration of Independence and the US Constitution were both debated and signed.

The 78-year-old Argentine pontiff — the leader of the world’s 1.2 billion Catholics — said the “ringing words” of the Declaration, adopted in 1776, still inspired people around the world today.

He specifically emphasized the importance of religious freedom, “a fundamental right which shapes the way we interact socially and personally with our neighbours whose religious views differ from our own.”

Blasting “various forms of modern tyranny” that “seek to suppress religious freedom… or to use religion as a pretext for hatred and brutality,” Francis urged those of all faiths to work together for “peace, tolerance and respect for the dignity and rights of others”.

He paid homage to the Quakers, Protestants who founded Philadelphia in the 17th century, lauding their “profound evangelical sense of the dignity of each individual and the ideal of a community united by brotherly love”.

“That sense of fraternal concern for the dignity of all, especially the weak and the vulnerable, became an essential part of the American spirit,” he said.