OCCUPIED JERUSALEM: Masked Palestinians whirling slingshots clashed with Israeli riot police in two Arab neighborhoods of Occupied Jerusalem Saturday after the shooting death of a teenage stone thrower. It was a sign of rising tensions on the eve of Palestinian commemorations of their uprooting during Israel's 1948 creation. The possibility of escalation comes at a critical time for US Mideast policy. President Barack Obama's envoy to the region, George Mitchell, resigned Friday, and the US president may now have to retool the administration's incremental approach to peacemaking. Obama is to deliver a Mideast policy speech in the coming week. Palestinian officials argued that Mitchell was destined to fail because of what they said is a faulty US premise – that Israelis and Palestinians are equals who can be nudged by a persistent mediator. As the occupier, Israel holds all the cards and only US pressure on Israel will yield results, said Nabil Shaath, a veteran negotiator. Meanwhile, Palestinian President Mahmoud Abbas told the Rome daily La Repubblica in an interview published Saturday that if Israel doesn't want to negotiate with a new Palestinian unity government that includes Hamas, “we'll go to the UN in September and ask if our people, which is again united, finally has the right to be a state.” With much at stake, it appears unlikely that Abbas' security forces will allow Sunday's commemorations to get out of hand. The day marks the anniversary of what the Palestinians call the “Nakba,” Arabic for “catastrophe,” referring to their displacement during the Mideast war over Israel's May 15, 1948, creation. On Saturday, the main flashpoint was Occupied East Jerusalem, annexed by Israel after the 1967 Mideast war and claimed by the Palestinians as their capital. A 17-year-old Palestinian, Milad Ayyash, was shot and critically wounded Friday during a clash near a Jewish settler enclave in East Jerusalem's Arab neighborhood of Silwan, according to a local activist, Fahri Abu Diab. Abu Diab, citing witnesses, alleged that shots were fired from the rooftop of the Beit Yonathan settlement enclave toward the stone throwers. An official at Jerusalem's Mukassed Hospital said Ayyash arrived with a bullet wound in the abdomen and bled profusely. Ayyash died of his injuries early Saturday. During Ayyash's funeral procession, Palestinians with scarves covering their faces broke away from hundreds of mourners, twirling slingshots to stone settler homes, passing cars and border police. Riot police fired tear gas, dispersing stone throwers who then would rejoin the procession, only to break away again later. Clashes also erupted at the Qalandia crossing. Dozens of Palestinian teens hurled stones, while some 150 Israeli soldiers took up positions on the rooftops of nearby building, occasionally firing tear gas.