Stanavforlant 1980. BNS Westdiep (F911), HNLMS Van Speijk (F828), HMS Juno (F52), FGS Schleswig-Holstein (D182) and USS Sellers (DDG 11). Standing NATO Maritime Group One (SNMG1) is one of NATO's standing naval maritime immediate reaction forces. SNMG1 consists of four to six destroyers and frigates. Its role is to provide NATO with an immediate operational response capability. In late November 1966, U.S. Rear Admiral Richard G. Colbert prepared a concept paper proposing a permanent Allied Command Atlantic naval contingency force based on Operation Matchmaker, an annual six-month exercise involving ships from NATO navies. The proposed contingency force was approved by NATO in December 1967 and activated in January 1968 as Standing Naval Force Atlantic (STANAVFORLANT). During the 1990s, STANAVFORLANT was heavily involved in Operation Maritime Monitor (July 1992 to November 1992), Operation Maritime Guard (November 1992 to June 1993) and Operation Sharp Guard (June 1993 to October 1996), the maritime embargo operations in the Adriatic Sea established to ensure compliance by Serbia and Montenegro with United Nations (UN) resolutions 713, 715, 787, 820 and 943. Between November 1992 and June 1996 some 74,000 ships were challenged, almost 6,000 were inspected at sea and more than 1,400 were diverted and inspected in port. The force was re-designated Standing NATO Maritime Group 1 in January 2005.