The 1979 Egypt-Israel Peace Treaty stipulated that the boundary was the “[r]ecognized international boundary between Egypt and the former mandated territory of Palestine.” A disagreement arose between the Egyptian and Israeli surveyors as to the correct location of parts of the mandatory border, however. Egypt claimed that Israel was refraining from complete withdrawal from Sinai, and therefore refused to normalize relations with Israel. The issue also became one of internal Israel politics, with the right wing led by Yitzhak Shamir taking a hard line on the issue and the left-wing Labour Movement led by Shimon Peres being more willing to compromise. Egypt’s claim relied on existing pillars, and Israel relied on the 1906 agreement between Britain, as the administrator of Egypt, and the Ottoman Empire, which ruled Palestine. The majority award of the Tribunal held that it would decide the location of the pillars “as it was demarcated, consolidated, and commonly understood during the period of the Mandate,” which was “the critical period.” As to the site advanced by Egypt, the Award admitted that “there is no evidence with respect to the erection of this pillar in 1907–07 nor with regard to its existence in the following years”; however, “throughout the critical period until a time after 1967 there was a boundary pillar at the location which during this whole period was considered to be a boundary pillar.” “Where the States concerned have, over a period of more than fifty years, identified a marker as a boundary pillar and acted upon that basis, it is no longer open to one of the parties or to third states to challenge that long held assumption on the basis of an alleged error.” “The principle of the stability of boundaries, requires that boundary markers, long accepted as such by the States concerned, should be respected and not open to challenge indefinitely on the basis of error.” The dissenting opinion of Ruth Lapidoth held that that “Egypt and Great Britain adopted the boundary line of the 1906 Agreement, without reference to any changes on the ground which may have occurred subsequent to that Agreement.” According to Lapidoth, “The majority erroneously attributes stability to boundary markers whereas the principle of stability and permanence applies not to markers but to boundaries lawfully established and recognized.” Since the arbitrators were not authorized to choose a location for a pillar not advanced by the parties, the final pillar on the seashore was not determined and, after the arbitration was concluded, the parties negotiated its location.