Canada’s Minister of the Environment and Climate Change Catherine McKenna has said that the US actions in subjecting the Canadian plane maker Bombardier to huge tariffs was "completely without merit" and "another example of protectionism".

US authorities had imposed 300% tariffs on imports of Bombardier C-Series jets following complaints by its US-based rival Boeing, that Bombardier had dumped its C-Series jets at "absurdly low" prices.

The row threatens more than 4,000 jobs at Bombardier's Belfast plant, where parts for the C-Series jet, including the wings, are made.

The US government has said that its intervention was prompted by concern to prevent "injurious dumping" of imports into the country, "establishing an opportunity to compete on a level playing field". Dumping means the export of a product at a lower price.

Speaking on RTÉ’s Morning Ireland, Ms McKenna said the allegations by Boeing "when they don't have a competitor plane" are very unhelpful.

She praised Ireland's strong commitment to trade and said she was delighted Minister for Foreign Affairs Simon Coveney said the US position on Bombardier was unacceptable.

She said he had very firmly sent a message to the US that "this threatens jobs" at the Bombardier in Northern Ireland.

Ms McKenna said that Canada is fighting hard against the "unacceptable" measures.

She said that the "US doesn't seem to accept that trade is a good thing".

On Wednesday, Canadian Prime Minister Justin Trudeau raised the row with US President Donald Trump.

He said he told Mr Trump that the decision to impose the tariffs was a ‘Block’ to Canada making any military purchases from Boeing.