President warns Trump that US underpins world order

US President Barack Obama made a strident case for his successor Donald Trump to retain Americas support for a liberal world order Sunday, warning world peace and prosperity depend on it.

"The main advice that I give to the incoming president is the United States really is an indispensable nation in our world order," Obama said in Peru as he wrapped up his final foreign visit.

The United States' ability to uphold "international norms and rules. That's what's made the modern world," Obama said, admitting that Washington had not always fulfilled its own ideals, but remained vital to global security.

But he argued history served as a warning for those imagining or flirting with a revised global order.

"Take an example like Europe before that order was imposed. We had two world wars in a span of 30 years. In the second one, 60 million people were killed. Not half a million, not a million but 60 million. Entire continents in rubble."

"We're not going to be able to handle every problem, but the American president and the United States of America, if we're not on the side of what's right, if we're not making the argument and fighting for it even if sometimes we're not able to deliver it 100 percent everywhere, then it collapses."

"There's nobody to fill the void. There really isn't," he said.