Arms Megadeal Collapsed When China, Russia Links Emerged

American defense giant RTX and a Saudi weapons firm were heading toward a multibillion-dollar deal when it was abruptly called off early this year. The reason, say people familiar with the talks, was RTX’s concerns that its Saudi partner’s companies were pursuing business with sanctioned Chinese and Russian entities.

That unease was a deciding factor for an advisory board of retired American military officers to resign from the Saudi company, Scopa Defense, the people said. Scopa fired its American chief executive who had raised the sanctions concerns with his company’s...