Global index provider MSCI announced Thursday it will expand the weight of China A-shares in the benchmark Indexes by quadrupling the inclusion factor from 5 percent to 20 percent in three steps, a move expected to draw a surge of fresh foreign capital into the world's second-largest economy.

According to the announcement on the indexer's website, the addition will happen in May, and the yuan-denominated A-shares will ultimately see their weighting shoot up to 3.3 percent in the MSCI Emerging Markets Index from the current 0.72 percent, as the inclusion factor increased to 20 percent in November.

Shares on ChiNext board, which mainly lists high-tech companies and those with high growth potential, will join MSCI indexes for the first time.

Upon completion of the decision, "there will be 253 Large and 168 Mid Cap China A-shares, including 27 ChiNext shares, on a pro forma basis in the MSCI Emerging Markets Index", said the announcement.

"Stock Connect has proven to be a robust channel to access A-shares. The successful implementation of the initial 5 percent inclusion of China A-shares has been a positive experience for international institutional investors and has fostered their appetite to increase further their exposure to the mainland China equity market," Remy Briand, MSCI managing director and chairman of the MSCI Index Policy Committee, said in the announcement.

"The strong commitment by the Chinese regulators to continue to improve market accessibility, evidenced by, among other things, the significant reduction in trading suspensions in recent months, is another critical factor that has won the support of international institutional investors."