England and Scotland came fifth and sixth in a league table showing fighting among 11 to 15-year-old schoolgirls in 35 developed countries.
In both countries, almost a third had been involved in at least one physical fight in the previous year. Concerns have been raised that Britain's "ladette" culture is fuelling such problems.
Dr Candace Currie, the director of the child and adolescent health research unit at Edinburgh University and co-author of the report, said the high level of fighting among girls in the UK worried her.
The average rate of girls' violence across all the countries was just 23 per cent, while worst-scoring Hungary was not far ahead of the English and Scottish on 32.1 per cent.
After that came Estonia, Lithuania and Belgium. Wales fared slightly better in 12th place and a score of 24.6 per cent, while Finland did best with 13.3 per cent.
The study, which quizzed 161,082 pupils, found that while boys were more violent overall, British schoolboys were further down the table than their female counterparts. Scottish boys fared worst, earning 10th place with a rate of 60.2 per cent, while those south of the border were not far behind in 13th, and a score of 59.2 per cent. Welsh youngsters only came 26th, with 53.3 per cent of boys having been in a fight.
The researchers reported that girls were most likely to fight with friends and family members, while boys were much more likely to engage in violence with total strangers.
They said fighting among youngsters could be an sign that they would go on to be more violent, and called for a reduction in violent imagery in the media. More research was also needed to address the growing problem, they added.
The study, by child health experts from Canada, Scotland, Poland, Israel and America and published in the journal of the American Academy of Paediatrics, is based on research from 2001/02.
After seeing the Current Canadian Election Results Rush, me thinks this study is flawed. I mean US not even on the list?