China is to treble the amount of money foreigners can invest in the mainland capital market, making the long-awaited announcement on the eve of this week’s high-level Sino-US economic summit. China’s foreign exchange regulator, the State Administration of Foreign Exchange, said on its website Sunday that the quota for registered foreign investors would be increased from $10bn to $30bn, although it could be several months before institutional investors secure fresh quotas. The move comes amid signs Beijing is poised to permit further foreign investment in the domestic securities industry. The FT reported last week that Credit Suisse and Morgan Stanley had each signed agreements with Chinese partners for mainland investment banking ventures, and now Citigroup, Merrill Lynch and JPMorgan are among other US investment banks discussing potential partnerships with mainland securities firms.