The firm is 60% owned by French state rail firm SNCF.
The UK government sold its stake in the business to private companies for £757m in 2015.
"We are frustrated by the Federal Aviation Administration's inability to do what nearly 40 countries have done, which is to safely deploy 5G technology without disrupting aviation services, and we urge it do so in a timely manner," the firm said in a statement.
"Let's be honest, nobody, nobody cares about what's happening to the Uyghurs, okay? You bring it up because you really care. And I think that's really nice that you care but .... The rest of us don't care. I'm just telling you a very hard truth," he said.
The employment rate for people aged between 50 and 64 has been increasing steadily since the mid-1990s, and in April to June 2021 stood at 71.2%, according to official figures. However, that increase has lagged behind younger age groups in the pandemic.