The no-shows at Sibos are spilling into other high profile events, including the World Bank and IMF meetings next week in Tokyo, as China's dispute with Japan over sovereignty of a number of islands in the East China Sea escalates.

Swift has confirmed that Industrial and Commercial Bank of China, Agricultural Bank of China and Bank of China have withdrawn all speakers and delegates from Sibos, but insists that advance bookings stay "ahead of target".

The annual Sibos event usually attracts up to 7000 participants, although registration at this year's show was expected to falter as Western vendors and banks from Europe and the US tightened budgets and sent smaller crews.

When Sibos was last in Asia Pacific in Hong Kong, Swift boosted the numbers by shipping in large numbers of banks from the Chinese mainland on day passes.

A Sibos boycott by Chinese banks will have an impact on the strategies of the large Western transaction banks, such as Deutsche Bank and JPMorgan, which had geared up for a show of their expertise in managing cross-border flows of Remnimbi payments at the event.

Swift says that delegates from China, both from local Chinese institutions, as well as foreign institutions operating in China, were expected to make up about five per cent of the total Sibos audience in Osaka.

In a statement, the interbank group says: "As regional Asia Pacific registrations are typically done closer to the event, it is too early to make any definite statement on Asian registration levels."