The Economist uses an expression “...the row is hotting up...” for intensification of international claims in the Arctic.
I think that in the US we would expect to hear ‘’ ...the situation is heating up..” (There are a lot more Google hits for heating up but that don’t mean much as many things other than international situations heat up.)
I’m assuming that “hotting up” is a British expression. Is that correct?
I assume that “heating up” is a US expression. Is that correct? What do other English speaking countries say?
The history of the two expressions might be interesting.