Facebook founder Mark Zuckerberg visited the headquarters of Russian leading Internet search engine Yandex to hold talks with its management, a source familiar with the matter said on Tuesday.

Yandex press secretary Ochir Mandzhikov declined to comment on the information.

Zuckerberg, worth an estimated $12 billion, has arrived in Moscow to connect with Russian start-up developers to beef up Facebook’s global presence and recruit Russian talent for the company.

Zuckerberg met with Prime Minister Dmitry Medvedev on Monday to discuss the social media giant’s potential cooperation with Russia’s burgeoning innovation sector.

After their meeting, Zuckerberg reportedly presented Medvedev with a T-shirt featuring the URL address of the prime minister’s Facebook page.

At a Facebook World Hack conference held on Monday evening in Moscow, Zuckerberg urged software developers to create new applications for his social network, the world’s largest, which would enable them to get access to almost 1 billion users.

Yandex and Facebook have been cooperating for several years. The Russian Internet search engine carries out Facebook account searches and some of the company’s services have been integrated with the U.S. social network giant.