From Longman Dictionary of Contemporary Englishwatching briefˈwatching ˌbrief noun [countable] British English SCLinstructions to someone to watch a situation carefully but not to become involved in it One of his responsibilities is to keep a watching brief on foreign broadcasts.
Examples from the Corpus
watching brief• The Economics and Industry Group has a watching brief on the state of the brewing industry.From Longman Business Dictionarywatching briefˈwatching brief when someone is given the job of watching the progress of part of a business, a series of events, or a court case for someone elseHe has been hired to keep a watching brief on the company’s road transport operation. → brief 