The sources said officials were looking at scenarios ranging from a straightforward win by either Republican President Donald Trump or Democratic opponent Joe Biden to more complicated outcomes where the result is contested or delayed.

Insiders cite concern in Ottawa about the potential for economic disruption to highly integrated supply chains, especially for the auto industry. Canada is particularly vulnerable, given that 75% of its goods and services exports go to the United States.

Prime Minister Justin Trudeau’s office declined to comment on the scenarios.

Canada’s ambassador in Washington, Kirsten Hillman, is playing a central role, said the sources, who requested anonymity given the sensitivity of the situation and declined to give precise details as to what they were looking at. Hillman’s office declined an interview request.

Trudeau said Canada was looking at political polarization in the United States with some concern.

“We’re all watching the U.S. election with close attention because of its potential impact on the Canadian economy and on Canadians,” he told reporters on Thursday.

“If it (the result) is less clear there may be some disruptions and we need to be ready for any outcomes,” he said.

Canadian officials are also looking at what happened in the disputed 2000 U.S. election, which took five weeks to resolve in favor of George Bush. Despite the tensions, there was no political violence.

But Trump has questioned the integrity of the electoral system many times, prompting apprehension about what his supporters might do in case of a contested or unclear result. That said, Canadian officials are not looking at extreme scenarios.

“I doubt anyone seriously would consider a flood of people making a mad dash to the border no matter how bad it gets,” said one person familiar with the discussions inside Ottawa.

Colin Robertson, a former Canadian diplomat with several U.S. postings, said contacts at the foreign ministry told him they had already sent a memo on the matter to members of Trudeau’s team.

“There has been some concern from the prime minister’s office about ‘What if things went very badly, what might we do?’,” said Robertson, who is also vice president of the Canadian Global Affairs Institute.

Robertson said he had been told the concern was largely from people who had not served in the United States and therefore had a less deep understanding of U.S. institutions.

In public, Canadian officials are taking a neutral tone.

Trudeau, who has clashed with Trump in the past, said last week that Canada was respectful of events south of the border.

“We will not be interfering or engaging in any way in their electoral processes and that includes commenting on their electoral processes,” he told reporters.

Trudeau’s team was left scrambling in 2016, as no one had predicted a Trump victory, and it rushed to respond to the implications the day after the election, according to two people directly familiar with the matter.

University of Ottawa international affairs professor Roland Paris, Trudeau’s first foreign policy advisor, said Ottawa was right to stay out of U.S. politics.

“Trump has a clear track record of retaliating vindictively against anyone who says things that he doesn’t like,” he said.