The copying of Prince Charles' diaries by a former member of his staff was "blatant, outrageous and wrongful", his lawyers have told the High Court.
The prince made unflattering comments about Chinese diplomats
They are trying to stop the Mail on Sunday newspaper from making further disclosures from the copied versions.
The prince criticised Chinese diplomacy in the journals - from his visit to Hong Kong for the 1997 China handover.
The paper's owner Associated Newspapers agreed not to publish anything further before the next hearing in February.
Legal action was launched last month after the newspaper published extracts in which the Prince of Wales described Chinese diplomats as "appalling old waxworks".
The prince called his 3,000-word journal the Handover of Hong Kong - or the Great Chinese Takeaway.
He described one ceremony as an "awful Soviet-style" performance and allegedly dismissed a speech by then-Chinese President Jiang Zemin as "propaganda".
Hugh Tomlinson QC, representing the prince, said the article was "an unjustified publication of misappropriated documents of a personal nature".
Mr Tomlinson said he was trying to "draw the line as tightly as we can" around the journals before the main hearing in February.
Mark Warby, QC for Associated Newspapers, said the Mail on Sunday had already agreed not to publish more details before the next hearing.
'Breach of confidence'
Mr Tomlinson said a number of the prince's private journals were "wrongfully copied by a former employee in the prince's private office", before falling into the hands of journalists.
"It is a blatant, outrageous and wrongful interference with material from the prince's private office."
Britain handed Hong Kong back to China after its 'lease' ended
The prince's lawyers claim the Mail on Sunday article was a breach of confidence and infringement of his copyright and are seeking the return of the copied journals.
The prince is said to regularly write journals of his official visits, with around 100 copies being circulated to friends, relatives and contacts.
Details from the diary were published only days after an official visit to the UK by Chinese President Hu Jintao.
This is not the first time the Royal family has found itself in dispute with the UK press.
In November 2003, the Queen won a permanent injunction against the Daily Mirror, preventing it from publishing further details about journalist Ryan Parry's employment as a footman at Buckingham Palace.
Earlier this year, Prince Charles audibly voiced his dislike of facing the media at a photo call, during his annual skiing holiday at Klosters, in Switzerland, and called BBC reporter Nicholas Witchell "awful".