The Organisation for Economic Cooperation and Development is considering coming up with a code of conduct for banks on how they help clients with taxes, a senior official said on Wednesday.

We could develop, with the banking sector, a code of conduct in the tax sector, Jeffrey Owens, who heads the OECD's tax division, told reporters on the sidelines of a private banking conference in Singapore.

The code of conduct will involve all banks with a lot of emphasis on investment banks, he said.

He said the idea was still being discussed and could be put up for discussion at a meeting in September.

UBS settled a U.S. tax probe last year after it emerged that it had helped rich Americans hide money in secret Swiss accounts, but banking secrecy in top wealth management center Switzerland and elsewhere is still under pressure.

The OECD has been pushing financial centers around the world to be more transparent in a bid to combat tax evasion, and has put some on a gray list of countries that have not fully implemented internationally agreed tax standards.

Owens also said the OECD has begun a peer review process of laws regarding information exchange of 18 jurisdictions, including Bermuda, the Cayman Islands and Jersey, and that the initial reports could be out before of the year.

World leaders agreed at a G20 summit in London last year to crack down on tax evasion and banking secrecy, and the group asked the OECD to publish and update lists of tax havens.

Singapore, which met OECD tax standards last year, has been promoting itself as a base for banks such as UBS, Credit Suisse and Citigroup to manage money for rich local and foreign clients.

(Reporting by Kevin Lim and Saeed Azhar; Editing by Neil Chatterjee)