Chinese start-up Luckin Coffee has completed its Series B+ round of financing worth 150 million U.S. dollars, the company said Thursday.

The funding, among which 125 million U.S. dollars are invested by BlackRock, which came four months after the coffee chain picked up 200 million U.S. dollars in investment, lifts the company's valuation to about 2.9 billion U.S. dollars, according to the company's statement.

As an emerging market player that rivals Starbucks, Luckin Coffee started trial operation in January last year, selling coffee at brick-and-mortar stores while also delivering products by online orders.

The Xiamen-headquartered coffee chain upstart has been expanding at a fast clip since its official operation in May 2018, with over 2,000 outlets opened in 36 Chinese cities by April 10.

Luckin plans to open 2,500 new stores in 2019, with total stores topping 4,500 by the end of this year, overtaking Starbucks to become the country's most popular coffee chain brand in terms of number of outlets and cups of coffee sold.

Once a major consumer of tea, China has seen an expanding coffee consumption market, which is expected to be worth about 1 trillion yuan (about 149.2 billion U.S. dollars) by 2025, according to an industry report.