The young man, reportedly a Spaniard named Victor Moreno who works in Copenhagen as a hairdresser, approached Carles Puigdemont as he was breakfasting at a shopping centre café.
Thrusting the Spanish flag towards the Catalan leader he said: "How do you like it?"
Goodnaturedly, a smiling Puigdemont said he had "no problem" with the flag and when invited to give it a kiss, he did. Twice.
The man, who filmed the encounter on his mobile phone and then approached La Vanguardia newspaper to publish the clip, ended the meeting with the retort: “A Spanish jail is waiting for you”.
Puigdemont later republished the clip from his Twitter account explaining:
“Some day they'll understand that the problem is not with Spain or with the flag. The battle is against those who exercise power despotically. Democracy is more important than all borders, all flags and all constitutions.”
Algun dia entendran que no tenim cap problema amb Espanya ni amb la seva bandera. La batalla és contra qui exerceix el poder despòticament. La democràcia és més important que totes les fronteres, totes les banderes i totes les constitucions https://t.co/IIMbicLt43— Carles Puigdemont 🎗 (@KRLS) January 23, 2018
Puigdemont arrived in Denmark on Monday morning to take part in a debate on Catalonia at the University of Copenhagen and to meet with Danish politicians to discuss the issue.
He has been in Belgium since October after he was sacked by Madrid and his government suspended following a unilateral declaration of independence in the wake of an illegal referendum.
Puigdemont faces arrest if he returns to Spain, where he is charged with rebellion, sedition and misuse of public funds over his role in Catalonia's independence drive.