HONG KONG, May 9 (Xinhua) -- The Belt and Road Initiative, with an emphasis on infrastructure development, "fits well" into the world's pursuit for sustainable economic development, participants at a United Nations forum said here Tuesday.

"Since the 2008 global financial crisis, there has been a global emphasis on the importance of infrastructure investment as a way of raising the productivity of economies and driving international trade in a sustainable way," said Chris Heathcote, CEO of Sydney-based Global Infrastructure Hub.

"One of the reasons the world is so interested in the Belt and Road Initiative is that it fits well into the context," he said at the International Public-Private Partnerships (PPP) Forum co-held by the United Nations Economic Commission for Europe (UNECE) and Hong Kong City University (CityU).

The forum, themed "Implementing the United Nations 2030 Agenda for Sustainable Development through effective, people-first PPP", included a high-level debate on how the international community could support China to operationalize the Belt and Road Initiative. The debate was participated by representatives from governments, international institutions as well as academic organizations.

In her inaugural remarks at the forum, Yvonne Choi, commissioner for Belt and Road of China's Hong Kong Special Administrative Region, said the forum "is a timely and topical event, especially as we get here just a few days ahead of a high-level Belt and Road forum to be held in Beijing".

According to Choi, in the same year when the UN set the 2030 sustainable development goals, China released a document to outline its vision and action plan for the Belt and Road Initiative, which listed infrastructure development as one of the key areas of cooperation.

A study released earlier this year by the Asian Development Bank estimated the annual infrastructure investment requirement in Asia from 2016 to 2030 at around 1.7 trillion U.S. dollars, while the region's current investment level is only about half of that amount.

"The gap cannot be filled by public money alone, and this is where the PPP model comes in," Choi said.

"We all believe that infrastructure supports economic growth, but that dose not happen automatically," Danny Alexander, vice president of the Asian Infrastructure Investment Bank (AIIB), said during the debate, adding that challenges lie in making sure it is a right project that can support the growth, as well as in incorporating the needs of local people so as to remain sustainable.

He predicted that the Belt and Road Initiative "can be generally transformational" for related countries since it emphasizes on win-win cooperation with infrastructure linking these countries to enable trade growth.

Alexander, a former chief secretary of the British Treasury, stressed that "it is not only China that is talking about the importance of infrastructure investment", European countries including Britain has also emphasized the importance of connectivity.