Former President Barack Obama on Saturday warned against “aggressive” nationalism and the loss of tolerance and respect for others, pushing back against President Donald Trump’s policies without mentioning his successor by name.

“The world is at a crossroads,” Obama said at a speech opening the Fourth Congress of Indonesian Diaspora in Jakarta.

He said the world must fight “discrimination against people based on race or ethnicity or religion.”

Without that, Obama said, “We start seeing a rise in sectarian politics.”

“We start seeing a rise in an aggressive kind of nationalism,” he said. “We start seeing both in developed and developing countries an increased resentment about minority groups and the bad treatment of people who don’t look like us or practice the same faith as us.”

Obama said progress depends on those willing to “stand up for tolerance and moderation and respect for others.”

“If we begin to doubt ourselves and all that we have accomplished, then much of the progress that we have made will not continue,” he said. “What we will see is more and more people arguing against democracy, we will see more and more people who are looking to restrict freedom of the press, and we’ll see more intolerance, more tribal divisions, more ethnic divisions and religious divisions and more violence.”

“Let’s face it, if people do not show respect and tolerance, eventually you have war and conflict,” Obama said. “Sooner or later societies break down.”