From Sir Michael Arthur, president, Boeing Europe and managing director UK & Ireland

Sir, Boeing understands the concerns of the UK prime minister and the government about jobs in Northern Ireland. We are committed to the UK. We value the partnership, which stretches back almost 80 years.

The company has doubled our direct employment in the UK since 2011 and tripled our spending with more than 250 companies in the UK supply chain over the same period, to £2.1bn in 2016. More than 18,700 jobs in the UK are at Boeing or in the company’s tier one supply chain.

The company joined with the government in July 2016 to commit to doubling the size of our workforce again in the future, alongside even more opportunities for the supply chain in this country. For example, earlier this month Boeing broke ground for our first factory in Europe, in Sheffield. We are pleased to work with our partners, including the British government, and provide such a vote of confidence in the UK for the long-term.

The infographics shared with readers to illustrate the issues facing Bombardier (“US move against Bombardier risks reprisals”, September 28) refute the arguments made in the editorial “Boeing seeks protection in the guise of fairness” (September 28). They clearly demonstrate that Bombardier’s struggles predate this trade case and that the CSeries overlaps the Boeing 737 market.

The issue at stake is compliance with trade rules. An independent body in the US has found Bombardier to have violated them. Due to the weakness of its product in the marketplace Bombardier took action that prompted the International Trade Commission case. Boeing welcomes competition. Bombardier can sell its aircraft anywhere in the world. But sales must be made according to globally accepted trade rules. We share the commitment of the UK government to free and fair trade. That is what this case is about.

The World Trade Organisation has been engaged by Brazil to look into the support given to Bombardier. Judgements at the WTO have found the US and Boeing compliant with trade law. Boeing’s petition to the ITC seeks to restore a level playing field in the US single-aisle aeroplane market.

Boeing had to take action as subsidised competition has hurt us now and will continue to hurt us for years to come. We could not stand by, given this clear case of illegal dumping.