The 25-year-old singer proposed to the 36-year-old actress during a romantic trip to London for her birthday last month and he finally confirmed that they are engaged by posting a picture of them together with Priyanka wearing her diamond ring.
Nick captioned the sweet image: ''Future Mrs. Jonas. My heart. My love.''
She added the same picture and wrote: ''Taken... with all my heart and soul.''
Nick jokingly commented on her picture, writing: ''Wow congrats. He's the luckiest guy in the world,'' and their pal Gigi Hadid commented ''So happy for you two!!!!''
Speculation first mounted about an engagement after director Ali Abbas Zafar announced Priyanka was leaving the Indian film 'Bharat' and hinted that Nick had something to do with the decision.
He tweeted: ''Yes Priyanka Chopra is no more part of @Bharat_TheFilm & and the reason is very very special , she told us in the Nick of time about her decision and we are very happy for her ... Team Bharat wishes @priyankachopra loads of love & happiness for life (sic).''
The engagement comes as a surprise as the pair only started dating in May.
However, things got serious quite quickly for the couple during their whirlwind romance, after they introduced each other to their families.
Priyanka met Nick's parents at his cousin Rachel Tamburelli's wedding in New Jersey in June.
A source said at the time: ''It's a huge deal that Nick brought Priyanka to his cousin's wedding. He's dated a lot over the last couple years but it's never been anything serious, so this is a big step. Nick and Priyanka really like each other, and his family enjoyed getting to know her as well. She fit right in!''
And at the end of June, the actress brought Nick to India to meet her mother Madhu and they also attended Priyanka's friend's wedding.
Meanwhile, Priyanka recently spoke of her wish to start a family.
She said: ''I am a very 'live in the today,' maximum 'live in the next two months' kind of person. But [in] 10 years, I definitely want to have kids. That is, it's going to happen in the next 10 years. Well, hopefully earlier than that. I'm very fond of children and I want to be able to do that.''
The pair are currently in India for an engagement party.
It's believed the loved-up couple are throwing the lavish bash in her native country so that both sides of their families can mingle and get to know one another.