Thousands gathered in Egyptian cities on Friday to protest against Israeli air strikes on the Gaza Strip as Egypt's president vowed to support the enclave's people in the face of "blatant aggression".More than 1,000 people gathered near Cairo's al-Azhar mosque after Friday prayers, many waving Egyptian and Palestinian flags."Gaza Gaza, symbol of pride", they chanted, and "generation after generation, we declare our enmity towards you, Israel." "I cannot as an Egyptian, an Arab and a Muslim just sit back and watch the massacres in Gaza," said protester Abdel Aziz Nagy, 25, a member of the Muslim Brotherhood.Protesters were marching from other areas of Cairo towards Tahrir Square, the main rallying point for last year's uprising.In Alexandria, around 2,000 protesters gathered in front of a mosque, some holding posters demanding Egypt's border crossing to Gaza be opened to allow aid into the impoverished enclave.Hundreds also gathered in the Egyptian cities of Ismailia, Suez and al-Arish to denounce Israel's attacks. Thousands also marched in protest in Lebanon's biggest Palestinian refugee camp Ain el Hilweh on Friday.The protesters began their demonstration after Friday prayers, chanting slogans against Israel.Dozens of Palestinian gunmen participated in the march.Like many there, refugee Issam al Masri said that he came to support his brothers in Gaza, and that he hopes to one day see a liberated Palestine.In a separate protest in Beirut, dozens gathered in front of the United Nations headquarters, denouncing the Israeli offensive and calling on Arab countries to support Palestinians.In New York's Times Square, more than one hundred people gathered to support Palestinians in the Gaza Strip. On the other side of the world in Sydney Australia, supporters of Israel stood face to face with Palestinian supporters.And in Seoul South Korea, protesters gathered in front of the Israeli Embassy.