Global index provider MSCI's announcement that it will quadruple the weighting of large-cap Chinese shares in its benchmark indexes is likely to drive more money into the still highly regulated mainland market, investors and analysts said.

In a widely expected move, MSCI said Thursday that it will increase the weighting of China A-shares — yuan-denominated stocks traded on the mainland — from 5 percent to 20 percent in three steps to November of this year.

Chinese shares, which slumped sharply in 2018, have been on a tear this year, rising 14 percent in February alone on factors including optimism over progress in ending the U.S.-China trade war and expectations for the expanded MSCI inclusion.

Investors and analysts welcomed the news as a significant step in the broader opening of Chinese markets to international funds. They still remain subject to tight capital controls.

"Overall, the final inclusion plan continues to look as aggressive as its proposal, marking another milestone in China's capital market opening up," Citi China equity strategist Jerry Peng said in a note dated Thursday, adding that the U.S. bank expects "strong foreign inflows to China's onshore market."

Chinese A-shares were included in the MSCI Emerging Markets Index for the first time last year. Investors can access them through an arrangement between the Hong Kong and mainland Chinese markets.

Gao Ting, head of China strategy at UBS Securities, said in a note Friday that the MSCI changes would likely spur $67 billion in inflows to the A-share market this year alone.