Thousands of British passport holders in Hong Kong and on the mainland face being marooned because of little-known changes in renewal procedures.
Regulations introduced last August mean that the applications are dealt with in Hong Kong but the passports are issued from Britain.
Previous passports are cancelled as soon as the person applies for renewal, and the new passports are taking up to four weeks to arrive.
That means business people across Asia can be stranded and unable to travel while they wait.
One Hong Kong businessman was forced to spend HK$15,000 travelling to London to renew his passport or risk losing key deals in China and India because the Hong Kong processing centre could not guarantee the new passport would arrive before he travelled.
The regulations are also severely affecting British passport holders who commute between Hong Kong and the mainland on an almost daily basis. They have to renew their 10-year passports as often as every 10 months because they are full.