Brussels is remaining tight-lipped ahead of the looming March 31 deadline for countries to apply for founding membership of the China-proposed Asian Infrastructure Investment Bank.

Despite this silence, Switzerland and European Union member countries including the UK, Germany, France, Luxembourg and Italy are supporting Beijing's initiative to mobilize resources to improve Asia's infrastructure.

The decision of these European countries, which has annoyed the United States, may see the number of would-be founding members exceed 35 when the deadline arrives.