 In 1970, the Portuguese launched Operation Gordian Knot, which was initially successful at eliminating large numbers of FRELIMO guerrillas and their support bases in the north of the country; however, the redeployment of so many Portuguese troops to northern Mozambique allowed FRELIMO to intensify its operations elsewhere in the country.The following year, Portugal established an informal military alliance with Rhodesia and South Africa known as the Alcora Exercise.Representatives from the defence establishments of the three countries agreed to meet periodically to share intelligence and coordinate operations against militant nationalist movements in their respective countries.