The man behind Hong Kong's answer to the London Eye has sought to allay fears the big wheel project might never get off the ground, saying all the parts are now in the city and a soft launch is on schedule for September.

People willing to part with HK$100 will be able to view Victoria Harbour from 60 metres in the air from this autumn. 

The capability of the company chosen by the government to build Hong Kong's answer to the London Eye has been cast into doubt by a rival who lost out in the race to take on the big-wheel project.

The former Dutch foreign service employee, Raymond Poeteray, worked at the consulate in Hong Kong between 2004 and 2008. He faces charges of passing state secrets to Russian secret service SVR - the successor to the KGB - as well as bribery, laundering more than HK$870,000 and possession of a firearm.

A former Hong Kong-based diplomat accused of selling state secrets to Russia has been described as "the biggest Dutch spy in recent history'' by prosecutors in the The Hague.