NBCUniversal announced Monday that it has made an additional $200 million investment in BuzzFeed — on top of the $200 million it invested last year.

The funding values New York-based BuzzFeed at about $1.7 billion, according to a company rep, and brings it to nearly $500 million raised to date. News of NBCU’s doubling of its investment in BuzzFeed surfaced last month.

With the funding, the companies said they will extend their advertising-sales relationship. Under the expanded relationship, BuzzFeed will collaborate with NBCU’s Content Studio, which delivers short-form digital video content for advertisers specifically tailored to different platforms. NBCU also will sell BuzzFeed’s ad inventory, and the companies said they will work together to “create new digital consumer experiences” for NBCU premium content.

Jonah Peretti, BuzzFeed’s founder and CEO, said in a statement that the investment from NBCU “allows us to remain a fully independent company but have access to and resources from the strongest and best media company there is.”

BuzzFeed’s other investors include Lerer Hippeau Ventures, Andreessen Horowitz, New Enterprise Associates, RRE Ventures, SoftBank Capital and Hearst Ventures.

Following NBCU’s first equity stake in BuzzFeed last summer, the companies teamed on initiatives including BuzzFeed’s promotion of the 2016 Rio Olympics on Snapchat; co-selling ad deals across linear and digital; and content partnerships like featuring BuzzFeed’s Tasty on NBC News’ “Today.”

“Over the past year, BuzzFeed has proven to be a valuable partner across our business. From the Olympics to the record-breaking launch of ‘Secret Life of Pets,’ BuzzFeed has helped us engage millennial audiences with our content and extend the reach of our clients’ campaigns to new platforms,” Maggie Suniewick, president of NBCUniversal Digital Enterprises, said in a statement.

LionTree Advisors acted as financial adviser and Fenwick & West acted as legal adviser to BuzzFeed on the transaction. Davis Polk & Wardwell acted as legal adviser to NBCU.

Around the time of its original investment in BuzzFeed, NBCU also invested $200 million in Vox Media, whose sites include the Verge, SB Nation, Curbed and Recode.