Zwei-plus-Vier-Vertrag
The British insisted to the end, against Soviet opposition, that NATO be allowed to hold manoevres in the former East Germany. After the Americans intervened, both the UK and France ratified the Treaty on the Final Settlement with Respect to Germany in September 1990, thus finalizing the reunification for purposes of international law. Thatcher later wrote that her opposition to reunification had been an "unambiguous failure".