Did he sue him in British courts. The threshold for libel/slander of a public person is way different than here in the USA.
Donald Trump suing ex-MI6 spy Christopher Steele at High Court (UK)
Donald Trump is suing a former MI6 officer and the intelligence consultancy he founded, High Court records show.
The former US president is bringing a data protection claim against Orbis Business Intelligence and its founder Christopher Steele, who previously ran the Secret Intelligence Service’s Russia desk.
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Mr Steele and Orbis Business Intelligence were previously sued for libel by Russian national Aleksej Gubarev over the publication of the dossier, claiming they were legally responsible for BuzzFeed publishing the dossier.
However, in a judgment in October 2020, Mr Justice Warby dismissed the claim.