The OECD said the UK economy may need more stimulus and a further round of quantitative easing may be necessary.
The OECD said UK growth remained flat, and is only expected to "pick up momentum" towards the end of next year. The Paris-based economic think tank forecasts that the UK economy will grow just 0.9% this year, after shrinking 0.1% in 2012.
Angel Gurría, the OECD's secretary general, said a "particularly bright spot" in the UK was employment figures.
More top news
Facebook is to test a set of emoticons to add to the like button giving users more choice to react to their friends' status updates.
When you meet Malala Yousafzai it is hard to imagine such a shy, softly spoken girl addressing world leaders in the spotlight.
Nobel prize-winner and campaigner Malala Yousafzai speaks to ITV News about her political ambitions and her new Birmingham accent.