London mayor Sadiq Khan gave a nod to his challenger Count Binface at his swearing-in ceremony on Tuesday.
Mr Khan has started his historic third term after his election win over the weekend.
“It would be nice to take a moment to celebrate becoming the first person in British political history to win successive victories over Count Binface,” the Labour mayor said.
“Believe me, he made me work hard for it.”
Count Binface secured 24,260 votes in the London mayoral election, beating Britain First candidate Nick Scanlon, who stormed off the stage at the results ceremony while attacking Mr Khan’s record.
Mr Khan said Count Binface’s victory over the far-right party was “another reason to love London”.
Count Binface’s manifesto included scrapping the controversial video assistant referees from English football, banning loud snacks from theatres, and renaming London Bridge to Phoebe Waller-Bridge.
He has previously stood in contests including the Uxbridge by-election following the resignation of Boris Johnson.
Mr Khan received 1,088,225 votes (43.8%) to be re-elected as London mayor, a majority of nearly 276,000 over Tory candidate Susan Hall, who secured 812,397 votes (32.7%).