A Hong Kong-based toll road company will sell renminbi-denominated bonds to international investors this week in a little noticed deal that marks a big change in China's currency controls.

Hopewell Highway Infrastructure, controlled by Hong Kong tycoon Gordon Wu, plans to raise at least Rmb1bn ($150m) from institutional investors to finance the construction of expressways in China's Pearl River Delta region.

Hopewell is the first company other than a bank to issue renminbi bonds offshore, thanks to rules introduced by China this year to encourage greater international use of its currency.

“The issuance of the first renminbi corporate bonds by Hopewell marks a milestone in the development of renminbi business in Hong Kong,” said He Guangbei, chief executive of Bank of China (Hong Kong), which is arranging the deal.

“It not only helps diversify the renminbi bond offerings and deepen the local bond market but also strengthens Hong Kong's position as an international financial centre.”

Apart from the Hopewell deal, there have been just 13 renminbi bond sales in Hong Kong. All of them – apart from a Rmb6bn bond issued by the Chinese government – were issued by mainland banks and the onshore subsidiaries of foreign banks.

Hopewell – which is domiciled in the Cayman Islands and listed on the Hong Kong stock exchange – is not just the first non- financial company to issue renminbi bonds offshore; it is the first foreign entity to do so. “We see this as a very, very important deal from a number of angles,” said William Liu, partner at Linklaters, the legal adviser to Bank of China on the Hopewell deal.

“It opens a lot of possibilities,” he said. “I wouldn't be surprised if two years down the road we see, for example, an Indian company issuing a renminbi bond to pay for a Rmb3bn power turbine to be exported from China.”

The cascade of regulatory changes that enabled Hopewell to issue renminbi bonds offshore started in February, when Hong Kong's central bank set out the supervisory principles for renminbi bond issuance in the territory.

“People were puzzled” by the announcement at the time, said Mr Liu. Companies had no way to transfer the money from Hong Kong to the mainland. And even if that was possible, there was no way to move renminbi back from the mainland to repay investors in Hong Kong.

A partial solution to the problem arrived in June, when mainland regulators announced a dramatic expansion of the year-old pilot programme that allowed Chinese companies to settle cross-border trades using the renminbi.

Originally the scheme had been restricted to five cities within China, as well as Hong Kong, Macau and a handful of nations in south-east Asia. Now it covers 20 Chinese provinces and the rest of the world.

For companies looking to finance mainland projects through offshore renminbi bonds, there was an even more significant change. The scheme was expanded to include all sorts of current account transfers, including dividend payments from onshore projects. That means companies are now able to use profits from their mainland operations to repay renminbi raised from offshore investors.

But one problem is that Chinese regulators have not opened up capital account flows to the same extent. If a company wanted to transfer a large amount of renminbi from Hong Kong to the mainland, say to finance a project, it would need approval from Chinese regulators.

Hopewell has permission to move the proceeds of its renminbi bond back to the mainland. And, while there is no guarantee that regulators will treat others the same way, analysts are optimistic. “It can be done – that's the message coming out of the Hopewell case,” said Kelvin Lau, an economist at Standard Chartered.