In billions of dollars :

1. USA - 2380
2. European Union - 2112
3. China - 1950
4. United Kindom - 782
5. Japan - 776
7. South Korea - 514
8. Canada - 514
9. India - 467
10. Singapore - 373

Europe :

1. Germany - 1233
2. United Kingdom - 782
3. France - 659
4. Netherlands - 477
5. Italy - 435
6. Spain - 431
7. Belgium - 310

2013 data.

Source : WTO