Since the beginning of the regional turmoil and the regime change in Egypt,  there were Egyptian voices speaking of cancelling or reviewing the peace treaty  with Israel. Lately, after the terrorist attack in Sinai that killed 16 Egyptian  border guards, Mr. Mohamed Gadallah, legal adviser to the president of Egypt,  Mohamed Morsy, was quoted saying that the president is studying whether to amend  the Camp David accords to ensure Egypt’s “full sovereignty” over  Sinai.
Naturally, these expressions raise concern in the Israeli public.  However, let us put aside the political implications of these expressions to  examine international law: can Egypt legally change or cancel unilaterally its  peace treaty with Israel?
The peace treaty between Israel and Egypt has no  expiration date nor does it prescribe a procedure for its cancellation by one of  the parties. This treaty established the peace between Israel and Egypt on the  foundations of a full Israeli withdrawal from the Sinai Peninsula and the  Israeli recognition of full Egyptian sovereignty over Sinai. In the same breath,  the treaty established security arrangements, essentially creating limited force  zones, mainly in Sinai, and deploying an international force to supervise the  implementation of these security arrangements.
The peace treaty itself  allows the review and amendment of the security arrangements, at the request of  a party. However, amendments must be by mutual agreement.
Therefore,  Egypt may request that Israel review and amend the security arrangement. Israel  should consider such a future request in good faith, as required in the  implementation of treaties. It is worth mentioning that in the past, in face of  a change in security conditions in the Gaza Strip because of Israeli  disengagement from the Gaza Strip in 2005, Israel and Egypt agreed on a new  security arrangement. Under this arrangement, Egyptian border-guard forces, on  an agreed scale, have deployed on the Egyptian side of the Gaza Strip, where  only Egyptian civil police, armed with light weapons, were allowed to deploy  under the peace treaty.
This was done without derogation from the  treaty. Moreover, media reports suggest that where temporary security  needs justify the operation of additional forces, this pinpoint activity is  enabled through coordination channels with Israel. For example, publications  contend that Egyptian air force attacks against terrorist targets in Sinai,  after the terrorist attack mentioned above, were coordinated with  Israel.
Egypt can reasonably argue that the security circumstances in  Sinai have changed due to the establishment and strengthening of terrorist  strongholds in the Sinai by local and foreign organizations. It may well be that  taking on the weapons these terrorists possess is not possible using only police  forces and light weapons. However, any amendment Egypt may seek in the existing  arrangement must be proportional to the new threat in the scale of force, its  equipment and duration of deployment.
Egypt should remember that the  removal from the border of significant Egyptian military forces that may pose a  military threat to Israel was a paramount factor enabling Israel to cut the deal  and withdraw from Sinai while preserving its security needs. If negotiation  regarding amendment of the security arrangements takes place, Israel too could  address circumstances that have changed on the ground. For instance, the flow of  illegal migrants through the Egyptian-Israeli border, most of them from Eritrea  and Sudan, seeking employment in Israel, is also a new phenomenon not  anticipated when the treaty was signed. Israel can seek to establish new  security arrangements with Egypt to tackle this problem.
International  law determines that even a fundamental change of circumstances which has  occurred with regard to those existing at the time of the conclusion of a  treaty, and which was not foreseen by the parties, may not be invoked as a  ground for terminating or withdrawing from the treaty, unless some exceptional  conditions were fulfilled. In any case, international law specifically states  that such a cause cannot be grounds to terminate a treaty that establishes a  boundary. Egypt cannot hold the territorial gains achieved in the peace treaty  while shaking off its obligations under it.

Published in the Jerusalem Post, 27.8.2012

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