However, May imports were 13% higher than the year-earlier period.
Pellet deliveries in the first five months of 2015 increased to 2.2 million tonnes, 55% higher than the corresponding 2014 period.
The UK took receipt of 200,418 tonnes of US origin pellets in May, 37% lower on the month and 26% down on-year.
Deliveries from Canada increased to 121,336 tonnes in May, an 11-month high and 98% higher than a year earlier.
