Boris Johnson failed to disclose that he met a uranium lobbyist while prime minister before entering into a new business with a controversial Iranian-Canadian uranium entrepreneur, the Observer can reveal.

Johnson’s new company Better Earth Limited also employs Charlotte Owen, a junior aide with just a few years work experience whom he elevated to the House of Lords last year at the age of 29, sparking intense controversy.

Transparency campaigners say there appear to be “serious public interest questions to be answered” over the nature and timeline of Johnson’s relationship with his co-director, Amir Adnani, the founder, president and CEO of Uranium Energy Corp, a US-based mining and exploration company, championed by former Trump advisor Steve Bannon.