Barack Obama has warned that Donald Trump’s leadership poses a threat to the United States.

Amid a contentious national discussion about immigration raids and deportations, Obama delivered a speech Tuesday night at the Bushnell Performing Arts Centre in Hartford, Connecticut, criticising existing federal government tactics.

He started by raising concerns about a troubling decline in America’s adherence to democratic principles.

“If you follow regularly what is said by those who are in charge of the federal government right now, there is a weak commitment to what we understood – and not just my generation, at least since World War II – our understanding of how a liberal democracy is supposed to work,” Obama said, according to Connecticut Public Radio.