Matche for nested pattern

I've tried to construct a regexp pattern which correctly matchs for the nested structure. That is, the string "abc<p>def<p>ghi</p>jkl</p>mno" is matched by the regexp as "<p>def<p>ghi</p>jkl</p>", not as "<p>def<p>ghi</p>". Are there any standard tactics for such a regexp?