Hot Chinese smartphone company Xiaomi has raised a huge $1.1 billion round of funding that values it at $45 billion, it said today.

The funding had been reported for several days, but official confirmation of the round and the valuation came from Xiaomi chief executive and founder Lei Jun in a post on Chinese social networking site Weibo. Xiaomi has become the world’s third-largest maker of smartphones in the past year, in large part by offering low-cost devices with strong software that have been eating into Samsung’s market share in China.

According to earlier reports from the Wall Street Journal, investors in the latest round included Yuri Milner’s DST Global, All-Stars Investment, a fund run by a former Morgan Stanley analyst, and a private-equity fund associated with Alibaba chairman Jack Ma.