Agrément/Diplomatic accreditation ambassador Observations List of heads of government of Yemen List of Prime Ministers of the United Kingdom Term end September 9, 1983 Saleh Abdulla Muthana Saleh Abdulla Muthana Ali Nasir Muhammad Margaret Thatcher February 18, 1987 Ahmed Abdo Rageh Yasin Said Numan Margaret Thatcher May 22, 1990 May 22, 1990 Yemeni unification with Yemen Arab Republic. Yasin Said Numan John Major