A fourth investment link between Hong Kong and the mainland went online on Monday.

Swap Connect, which provides mutual access to interest rate swap markets, started off with northbound trading and an initial daily quota of 20 billion renminbi.

At a launch ceremony, CEO of Hong Kong Exchanges and Clearing Nicholas Aguzin said the latest connect scheme is a major component in the internationalisation of the yuan.

"From Stock Connect to Bond Connect to ETFs and now Swap Connect, the connect programme is an ecosystem that supports the two-way flow between China and the world," Aguzin said.

Chief Executive of the Hong Kong Monetary Authority Eddie Yue said the launch of Swap Connect is another milestone in financial co-operation between Hong Kong and the mainland.

"It will create favourable conditions for global investors to increase their participation in the onshore bond market, and carries special significance for enhancing the recognition of and confidence in RMB bonds in the international market," Yue said.