"Oh. It looks as though a certain cat is out of a certain bag. I'm very very happy of course but had hoped for a private wedding. Fat chance!" Fry wrote Tuesday, after news leaked in the British press.
Fry, 57, and Spencer, 27, filed paperwork related to their upcoming wedding at the register office in Dereham, Norfolk, near his hometown, reports the BBC.
The documents state the wedding will take place at the Breckland Business Centre, which houses the register office and has a ceremony room that can hold up to 40 people.
The paperwork lists Spencer's occupation as writer, according to the BBC, which believes the couple began their relationship last year.
In August, Spencer Tweeted a picture of himself in Italy with Fry and friends who included Emma Thompson, Fry's longtime pal.
"Pretty amazing evening tonight in lovely company in Florence!" Spencer captioned the photo. Fry, who can currently be seen onscreen in The Hobbit: The Battle of Five Armies, is something of a national treasure in the UK, where he narrated all seven Harry Potter audiobooks.
He has also been open about his struggle with bipolar disorder, which he explored in his Emmy-winning documentary, Stephen Fry: The Secret Life of the Manic Depressive. According to the BBC, he has also been open about a suicide attempt in 2012.
Yet the actor seemed nothing but elated on Tuesday, thanking fans on Twitter for the flood of well-wishes.
"Thank you all SO much for your kind congratulations. Deeply touched xxx" he wrote.
