The policies of a Trump administration are both the biggest downside and upside risks to the global economy, an international survey of companies by Oxford Economics has found.

While 38 per cent of respondent companies were hopeful for US growth to surge thanks to President-elect Donald Trump's fiscal stimulus program, 27 per cent feared Mr Trump would instigate a trade war between the US and China.

Companies around the world are uncertain about a Trump presidency. Credit:Anindito Mukherjee

"The fact that he does come up as the biggest upside and the biggest downside risk is the real sign that there's a lot of uncertainty around what he's going to do," said Sarah Hunter, head of Asia-Pacific macro consulting at Oxford Economics.

"The rhetoric through the election was obviously very anti-migration, anti-globalisation," said Ms Hunter. "But he gets elected and the first thing he announces is that he's going to implement a big fiscal stimulus around infrastructure investment, which came out of the blue."