Orlando Bloom and Katy Perry's relationship is more ''serious'' than ever.

The 'Pirates of the Caribbean' actor recently rekindled his romance with the 33-year-old singer after a year apart but it seems their time apart only affirmed their commitment to one another and their union is much ''stronger'' now.

A source told People magazine: ''Orlando and Katy are great. They are dating exclusively again and things seem more serious.

''They are both excited about it and don't want to hide, but at the same time they are trying to keep privacy as well.

''[Orlando] seems very happy. It's obvious that they both missed each other after their split.

''Their relationship seems stronger now. Orlando got sick of being single. Dating different women is not so alluring to him anymore.''

The couple spent the weekend in Rome, Italy, with Katy's mother Mary Hudson, and the 'Dark Horse' singer referred to Orlando as her ''darling'' when she revealed she was there to give a talk on meditation at the Vatican's fourth annual Unite to Cure conference.

Taking to her Instagram stories, she said: ''Happy Saturday everyone, I'm here in Rome at the Vatican, to speak on meditation. I'm with my momma, my darling [Orlando], and my manager, Steve! It's a great day! I am so excited!''

The 'Roar' hitmaker was dressed in black with a matching hat and veil as she met the leader of the Catholic Church, while the 41-year-old actor opted for a blue suit.

The couple - who are yet to confirm they are back together - also spoke with bishop Paul Tighe, the Secretary of the Pontifical Council for Culture, during the event.

Their trip to Italy comes just weeks after Katy hinted that she and Orlando were back together as she said she was ''spoken for'' and ''very happy.''

She said: ''I have been spoken for and speak for myself. And I'm very happy!''