No issue has been so thorny or so fundamental to the Israeli-Palestinian peace process as the Palestinian right of return.

Long dismissed by Israel as an unjustified threat to its existence, and sidelined by western policymakers, it has refused to go away. On the contrary, for the refugees it has an almost sacred quality.

These are the people who fled or were expelled by Israeli forces in the wake of Israel's establishment in 1948. At the time they numbered about 750,000, three-quarters of Palestine's Arab population, but today they are many more. In 2007, they and their descendants were estimated by the Badil Resource Centre for Residency and Refugee Rights at 7.6 million, 4.6 million of whom are UN-registered refugees.

The right of Palestinian return is enshrined in international law and historical precedent, and affirmed repeatedly by the UN. Resolution 194 was passed by the UN general assembly in December 1948 and called on Israel to repatriate those "displaced by the recent conflict" with compensation for their losses. The 1948 universal declaration of human rights states that those who leave their homes for whatever reason have the absolute right to return to them. This worthy precept has been applied often, most recently to the displaced Kosovans.

Yet no one has succeeded in the Palestinian case, one of the world's oldest refugee problems. This is due entirely to Israel's refusal to repatriate the refugees on the basis that it would destroy its Jewish character, and the west's implicit acceptance of this argument. In consequence, since the late 1990s a raft of proposals – collective or individual compensation, settlement in host societies, transfer abroad – have been put forward by Israel and western countries aimed precisely at preventing the right of Palestinian return to Israel.

A US proposal for settling some refugees in special areas on the Libyan-Egyptian border and in Iraq, and integrating the rest into the Arab host-countries with Arab funding, was reported in mid-2010. That such impractical ideas are increasingly circulating is an indirect acknowledgement of the right of return's potency even after 62 years.

However, it may not survive for much longer. The peace process that seeks a two-state solution may end up sacrificing the refugees. In a desperate bid to wrest Israeli concessions, Palestinian negotiators may yet play their last card and give up the right of return.

The 2002 Arab peace plan referred to a just solution for the refugees only under pressure from Lebanon. Beneath the rhetoric there is a quiet assumption that the return of refugees to Israel is impossible, and other plans must be devised. Many have already been persuaded by this logic. But this ignores the illegality of such strategies. The right of return is an individual right, and no one except the refugees themselves can negotiate it away.

In any case, the current Palestinian negotiators, unelected and unrepresentative of the refugees, cannot legally speak for them. If they do, and this passes muster, it will only compound the gross injustice committed in 1948, and perpetuate the conflict for decades to come.

Ghada Karmi is co-director of the European Centre for Palestine Studies at the University of Exeter

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