SEOUL - A senior US diplomat said it was up to individual countries whether to join a new China-led international development bank as media reports said a growing number of close U.S. allies were ignoring Washington’s pressure to stay out of the institution.

France, Germany and Italy have agreed to follow Britain’s lead and join the Asian Infrastructure Investment Bank (AIIB), the Financial Times reported, quoting European officials. The newspaper said the decision by the four countries to become members of the AIIB was a major diplomatic setback for Washington, which has questioned if the new bank will have high standards of governance and environmental and social safeguards. The bank is also seen as contributing to the spread of China’s ‘soft power’ in the region, possibly at the expense of the United States. EU parliament president Martin Schulz said he welcomed the four European nations joining the AIIB, but added the bank must conform to internationally accepted standards.

‘I find it good that they join,’ he told reporters while on a visit to Beijing. ‘If more member states would join I would find it even better. ‘There is one additional element. Such new organisations must answer to the requirements of international standards. That is quite important.’ China’s state-owned Xinhua news agency said South Korea, Switzerland and Luxembourg were also considering joining.

However, Chinese foreign ministry spokesman Hong Lei would not comment on which countries had applied to join, and repeated that the bank would be ‘open, inclusive, transparent and responsible’. On Tuesday, Washington’s top diplomat for east Asia signalled that concerns about the AIIB remained, but the decision on whether to join was up to individual nations.

‘Our messaging to the Chinese consistently has been to welcome investment in infrastructure but to seek unmistakable evidence that this bank...takes as its starting point the high watermark of what other multilateral development banks have done in terms of governance,’ US Assistant Secretary of State for East Asian and Pacific AffairsDaniel Russel said in Seoul. ‘Every government can make its own decision about whether the way to achieve that goal is by joining before the articles of agreement are clarified or by waiting to see what the evidence looks like as the bank starts to operate,’ he told reporters.