December 1970) and a strong relationship with North Korea. On 23 February of that year, he declared Guyana a "co-operative republic". Adopting a policy of autarky, he banned all forms of imports into the country, including flour and varieties of rice that had been integral to the diet of Guyanese. Burnham also nationalised the major industries that were foreign-owned and -controlled. By 1979 his policies had reduced the private sector's share in the economy to only 10%. In declaring the Co-Operative republic, Burnham replaced the Head of State, removing the British Monarch and installing Arthur Chung as the first president (in a mostly ceremonial role), though Guyana remained a member of the Commonwealth of Nations. Port of Spain Protocol On 18 June 1970 Burnham signed the Port of Spain Protocol with Venezuela. The protocol, in place for 12 years, promoted co-operation between the two countries on the Border Dispute in Guayana Esequiba. The protocol was not renewed after 12 years. Membership of the Non-Aligned movement Burnham, after attending the 1970 summit of the Non-Aligned Movement in Lusaka, Zambia, paid official visits to several African countries—Zambia, Uganda, Kenya, Tanzania and Ethiopia—over the period 12–30 September 1970. The Guyanese government remained fully involved in the African liberation movement throughout the 1970s. Burnham sent more than a hundred Guyanese public servants to various departments of the Zambian Government. Many Guyanese doctors, engineers, lawyers and secretaries worked in Southern African states throughout the 1970s. House of Israel In 1972, Rabbi David Hill arrived in Guyana. He established the House of Israel, a religious sect that the opposition would accuse of operating as a private army for Burnham's PNC. In 2014, Joseph Hamilton, a former House of Israel priest, testified that the House of Israel committed "oppressive and terrorizing acts on behalf of the PNC." 1973 general election In the 1973 general election, Burnham received 70% of the vote and 37 of the 53 seats in the National Assembly. It is generally accepted that Burnham had significant influence on the results of the elections, and the elections were fraudulent. During the transportation of ballot boxes by the military, the army shot dead two Indo-Guyanese poll workers, who became known as the "Ballot Box Martyrs". Shortly after the election, Burnham expanded powers of preventative detention, allowing for restrictions on movement, possession of firearms, and search without warrant. Declaration of Sophia On 14 December 1974, Burnham issued