Mohamed El-Erian said the rise of Donald Trump from reality television star to U.S. president elect, shows the increasing speed at which politics and financial markets can be disrupted.

“We are seeing one improbable after the other materialize” El-Erian, Allianz SE’s chief economic adviser, said Wednesday in an interview on Bloomberg Television. “And that speaks to something much bigger that’s happening on both sides of the Atlantic, which are fundamental changes in the way politics are conducted and therefore how the economy, finance and institutions will respond.”

Trump, a real estate mogul who campaigned against free trade deals, defeated Democrat Hillary Clinton, the former secretary of state, fueled by support from less educated voters. His victory follows by months the decision by U.K. voters to leave the European Union. The S&P 500 Index slipped 0.4 percent at 9:30 a.m. in New York after futures markets Tuesday night indicated there could be a steeper plunge.

“What we’ve learned is that we live in a world where the improbable can become reality very quickly,” said El-Erian, who is also a Bloomberg View columnist. “What we haven’t learned yet is how to price that in.”

El-Erian has cited the “politics of anger” as an impediment to growth by preventing consensus on fiscal stimulus and structural reforms. He said Wednesday that Trump should move ahead with his plans to boost infrastructure investment. It would be harder to implement other promises, such as dismantling the North American Free Trade Agreement or slapping tariffs on China, and Trump should refrain from those actions, he said. Finally Trump should focus on easing divisions, according to El-Erian.

“He needs to be able to communicate in a way that unifies this country because the other  message from last night is that the U.S. is deeply divided, and for him to be able to govern  well during his administration he’s going to have to have some unifying theme,” he said.

Mohamed El-Erian is the chief economic adviser at Allianz SE.