A BBC World Service opinion poll has found sharply higher overseas approval ratings for US President Barack Obama than Republican challenger Mitt Romney.

An average of 50% favoured Mr Obama, with 9% for Mr Romney, in the survey of 21,797 people in 21 countries.

Only Pakistan's respondents said they would prefer to see Mr Romney win November's election.

France was the most strongly pro-Obama (72%).

The survey was conducted by GlobeScan/PIPA between 3 July and 3 September.