BAE Systems, Europe’s biggest defence contractor, has missed out on a multi-billion dollar vehicle contract from the US Department of Defence, the second time it has lost a major US vehicle competition in as many months.

The news marks the latest in a series of setbacks in BAE’s US business unit, which makes up over half of all the company’s sales. At the end of June the head of BAE Systems’ US business resigned to take the top job at a rival defence company.