President Donald Trump on Thursday took more jabs at Canada and France on the eve of the G-7 summit.

In a tweet, Trump accused the U.S. allies of levying "massive tariffs" and creating "non-monetary barriers."

French President Emmanuel Macron in a tweet had threatened to exclude U.S. from a joint statement issued every year at the G-7 summit.

"The American President may not mind being isolated, but neither do we mind signing a 6 country agreement if need be. Because these 6 countries represent values, they represent an economic market which has the weight of history behind it and which is now a true international force," Macron tweeted.

On Friday, Trump is scheduled to attend the annual summit and meet with leaders from the U.K., Canada, Japan, Italy, Germany and France. The forum of industrialized economies takes place in Quebec this year.