I have tried tons of combinations without any luck:

I want to get this rule:

http://www.domain.com/uk/ -> index.php?country=uk

From Apache:
RewriteRule ^([a-z]{2,}/)$ index.php?country=$1
RewriteRule ^([a-z]{2,})$ index.php?country=$1
RewriteRule ^([a-z]{2}/)index.php$ index.php?country=$1

I tried in location /:
rewrite "^([a-z]{2}/)$" index.php?country=$1 break;
rewrite "^/([a-z]{2}/)$" index.php?country=$1 break;

What I'm missing?