FRANKFURT (REUTERS) - The European Central Bank (ECB) is willing to offer help setting up Europe's planned financial transaction tax to ensure the levy does not destabilise financial markets, the Financial Times quoted a policymaker on Monday as saying.

Germany and 10 other European Union member countries agreed in January to the tax on trading in financial markets, which they hope to launch in January 2014 to cover part of the cost of the financial crisis.

"We're willing to engage constructively with governments and the European Commission to ensure that the tax has no negative impact on financial stability," ECB Executive Board member Benoit Coeure told the financial daily.

While the ECB has not publicly commented on the tax, Bundesbank President and ECB Governing Council member Jens Weidmann said last month its introduction could impair the market for repurchase agreements, which is important for liquidity.