Jeremy Corbyn met the Prince of Wales on Wednesday but will not be watching the royal wedding live at the weekend.
The Labour leader – a republican – is due to address his party’s economic conference on Saturday, when Prince Harry and Meghan Markle tie the knot.
During Prime Minister’s Questions in the Commons, Mr Corbyn wished the couple “all the best” and thanked Prince Harry for his work on mental health.
Following the session, a senior Labour spokesman was asked if Mr Corbyn would be watching the royal wedding on television.
The spokesman replied: “There’s catch-up, isn’t there?”
He said the Labour leader was due to speak at an economics conference at the time of the wedding on Saturday, so would not be able to watch it live.
“He wishes them all the best and he is a particular admirer of the work Prince Harry and Prince William have done in relation to mental health issues,” said the spokesman.
Sources confirmed that Mr Corbyn met the Prince of Wales on Wednesday but would not go into detail about the circumstances of their meeting.
At PMQs, Prime Minister Theresa May offered her best wishes to the couple.
She said: “I’m sure the whole House will wish to join me in offering our best wishes to His Royal Highness Prince Harry and Meghan Markle on their wedding this Saturday and the very best for their future lives together.”
In light of Mental Health Awareness Week, Mrs May praised Harry’s “tireless work” in raising awareness about the challenges faced by service personnel as they move into civilian life.
Mr Corbyn joined Mrs May in sending his wishes to the couple and thanked Harry “for the work he’s done in highlighting the need to challenge the stigma surrounding mental health, and the ability of all of us to talk about mental health to ensure people don’t suffer in silence on their own – particularly young people who are so often grievously affected by this”.