U.S. President Donald Trump's chaotic trade war will loom large over Doug Ford's provincial budget, with experts saying billions in financial aid to impacted workers and businesses will throw a wrench in the premier's plan to balance Ontario's books next year.

Next month, Ford's Progressive Conservatives are expected to unveil their first budget since winning a third-straight majority government in February. The spending plan could be announced in the days after Finance Minister Peter Bethlenfal…