The King is to host political leaders at Windsor Castle, according to reports.
Charles is believed to have invited Prime Minister Sir Keir Starmer, as well as first ministers from the devolved nations to a dinner on Wednesday.
Some of the devolved leaders will stay the night at the royal residence before having breakfast there in the morning, GB News reported.
Downing Street has been contacted for comment.
The King accompanied by Prime Minister Sir Keir Starmer and Deputy Prime Minister Angela Rayner (Leon Neal/PA)
It will be seen as Charles’ second intervention in politics in a week after Sir Keir and Angela Rayner joined him on a rare joint engagement to see a housing project.
The King took the Prime Minister and his deputy on a visit to a Cornish development he inspired.
The joint trip came days before Sir Keir is expected to set out further measures as part of a pledge to build 1.5 million homes ahead of the next election.
The King, Sir Keir and Ms Rayner carried out three engagements in Nansledan, a 540-acre extension to the seaside town of Newquay.
The visit is understood to have followed conversations about housing over the past few months between Charles and Sir Keir, during which the Nansledan project was mentioned.
Buckingham Palace declined to comment.