Switzerland needs to close loopholes in its tax law if it is to comply with international standards, according to a review to be released soon.

The Swiss agreed in 2009 to drop long standing obstacles and introduce international transparency standards. But a peer review will tell Bern that Switzerland needs to implement policies which make it easier to identify tax dodgers before it can be given a clean bill of health. The recommendation will come at a meeting of the Global Forum on Transparency and Exchange of Information for Tax Purposes – a spin-off from the Paris-based Organisation for Economic Co-operation and Development – which functions as an international sounding board on tax matters.

The group, established to advance the fight against international tax evasion, will review progress by various countries, including France, Italy and the US. But the focus will be on Switzerland, the world’s biggest centre for privately held offshore assets and a bastion of bank secrecy.

The review will highlight an inconsistency between Bern’s agreement to implement OECD standards on tax co-operation and the failure of its latest double taxation agreements to do so. Differences revolve around the detail required to identify tax dodgers and trigger an official Swiss response. Bern acknowledged, in an embarrassing admission this year, that its new tax treaties drawn up since 2009 failed fully to reflect OECD standards. The Swiss finance minister promised in February to amend the legislation.

The peer review warns that matters could escalate if the changes, which could be opposed in the Swiss parliament, are not implemented by next year.

The issue of identification is seen as a test of Switzerland’s commitment. Failure to make the necessary changes, or a parliamentary blockade, could reignite international tensions over Swiss bank secrecy.

“Yes, they’ve promised to enter a new era of transparency and exchange of information but they haven’t done it yet. The last minute declaration from their government to act from now on is not credible,” said a foreign official, who did not wish to be named.

The US and France have praised Swiss efforts but some other countries, notably Italy, remain sceptical.

The Swiss describe the failure as an oversight – which has already triggered an internal inquiry in Bern. The Swiss federal tax administration was stripped of some of its responsibilities this month in favour of a new unit in the finance ministry because it had not grasped the political ramifications of the omission.

“The politically explosive nature of this issue was underestimated,” said the Swiss government, which denied any political motivation behind the lapse.