The former UK Prime Minister Boris Johnson has been using his publicly funded private office to manage lucrative commercial ventures, potentially breaching ethics and lobbying rules, according to a trove of leaked documents obtained by The Guardian.

The Boris Files, comprising over 1,800 emails, letters, invoices, and contracts from the Office of Boris Johnson, reveal how the former leader leveraged contacts made during his 2019-2022 tenure for private gain after leaving Downing Street.

The documents, covering September 2022 to July 2024 with some from his time in office, show Johnson earning approximately £5.1 million for 34 speeches worldwide, alongside deals with media outlets like the Daily Mail and GB News. These activities, managed through his taxpayer-subsidized company, raise concerns about violations of "revolving door" restrictions on post-ministerial business.

Key revelations include Johnson lobbying a senior Saudi official he met as prime minister to pitch a firm he co-chairs to Crown Prince Mohammed bin Salman.

He also received over £200,000 from a hedge fund after meeting Venezuela’s President Nicolás Maduro, contradicting claims he was unpaid.

During his tenure, Johnson held a secret 2020 meeting with billionaire Peter Thiel, founder of Palantir, months before the firm secured a role managing NHS data. Additionally, he hosted a Tory peer who funded his Downing Street flat refurbishment for dinner in November 2020, a day after the UK’s second Covid-19 lockdown began, potentially breaching pandemic rules.

The Office of Boris Johnson, established in October 2022, has claimed £182,000 in public duty costs allowance (PDCA) to cover staff salaries, meant strictly for public duties, not commercial work.

A Cabinet Office source confirmed these claims, prompting scrutiny over whether Johnson misused the subsidy. The files, obtained by the US non-profit Distributed Denial of Secrets (DDoS), also highlight security concerns, as their source remains unknown.

Johnson has not responded to requests for comment.

The disclosures draw parallels to the Greensill Capital scandal involving former PM David Cameron, fueling calls for tighter oversight of ex-leaders’ activities.