Israeli police are out in force at Jerusalem’s al-Aqsa mosque as Palestinian groups stage a day of protest over access to the holy site.The demonstration is taking place following Palestinian warnings of a general uprising. However, Israeli authorities say they are not treating the reported claims as serious. Palestinian fears of extremist Jews gaining entry have reportedly been the cause of recent clashes. The latest rise in tensions comes as the United States peace envoy, George Mitchell seeks to restart Israeli-Palestinian talks after ten months of inactivity. He is due to meet both the Israeli Prime Minister and the Palestinian President today. US officials say he will stress the urgent need for to advance the process but they have no expectation of a breakthrough.