Karlie Kloss Is Engaged to Joshua Kushner: 'Their Hearts Are Full'

Supermodel Karlie Kloss and her boyfriend Joshua Kushner are engaged after six years of dating!

A source close to the couple confirmed their engagement to PEOPLE, saying “He proposed a few weeks ago during a romantic weekend together in upstate New York.”

The source adds, “They’re both overjoyed and happily celebrating. Their hearts are full and they’re excited to build their future together.”

Kloss confirmed the news on Instagram posting a sunset selfie of her new fiancé. “I love you more than I have words to express,” she wrote. “Josh, you’re my best friend and my soulmate. I can’t wait for forever together. Yes a million times over 💍”

The 25-year-old model and founder of Kode with Klossy, who is the face of brands including Swarovski, Adidas, Estée Lauder, Express and Carolina Herrera, has been dating the entrepreneur and venture capitalist since 2012. But despite such public profiles, they’ve managed to keep their relationship relatively out of the spotlight – attending just a handful of red carpets together (including this year’s Met Gala) and sharing a few Instagram snaps of one another (like the adorable pic Kloss posted last month). And though she has said she likes “having a more private life,” she did share a sweet sentiment on Kushner’s 33rd birthday, writing “Happy Birthday to my love + my best friend in the Universe. Love you more than I can ever express @joshuakushner ❤️.”

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Kloss told PEOPLE in 2013 that she appreciated that Kushner was “so not in fashion. It’s really refreshing to leave all the fashion shows and shoots and chaos totally behind.” And they do so by jetsetting all over the world – in April Kloss posted an Instagram of the two riding an ATV in Jordan’s Wadi Rum desert with the caption “My ride or die ❤️“.

Kushner is the younger brother to Jared Kushner, a senior adviser to President Trump and brother-in-law to Ivanka Trump. Kloss doesn’t speak publicly about her political soon-to-be in-laws, but has said she voted for Hilary Clinton in the 2016 election.

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Prior to their engagement, a source tells PEOPLE that Kloss converted to Judaism in early June (a step Trump also took before her engagement to the elder Kushner brother). “She’s never been one to make decisions lightly,” the source says. “She spends a lot of time reflecting and learning.”

Right now the couple is off “happily celebrating” their engagement by vacationing in Italy, where they were spotted hanging with A-listers David Geffen and Sir Paul McCartney.