RAMALLAH (AFP) - Mahmud Abbas called on Thursday for concrete US efforts to deliver a Palestinian state, as crowds marked the sixth anniversary of Yasser Arafats death. The Palestinian president said he would hold US President Barack Obama, who helped relaunch direct peace talks in early September, to his pledge to seek the creation of a Palestinian state within a year. We consider this statement to be a commitment by President Obama, not just a slogan, and we hope that next year he wont say to us 'we apologise, we cant, Abbas said in an address to tens of thousands. In a speech delivered at Arafats grave site, where a new museum is being built to honour the veteran leader, Abbas vowed he would not negotiate while Israel continued to build settlements on Palestinian land. He pledged to uphold Arafats insistence that Palestinians would one day secure east Jerusalem as the capital of a Palestinian state and the right of return for refugees. Abbas defended that proposal on Thursday, despite a warning from US Secretary of State Hillary Clinton against unilateral steps. We are thinking of going to the Security Council, and that is considered a unilateral act on our part, but when they (the Israelis) take unilateral actions like the wall, incursions, assassinations, uprooting olive trees, that isnt considered unilateral, he said. In a sign of continuing Palestinian divisions, Hamas forces in Gaza banned public commemoration of Arafats death, and a senior advisor to Ismail Haniya, the head of the Hamas government in Gaza, criticized Abbass speech. Abbas speaks as a political analyst and not as a leader with the authority to make decisions, Yussef Rizq said in a statement. In Ramallah, the political capital of the West Bank, crowds waving Palestinian flags and the yellow banners of the Fatah party that Arafat founded poured into the square across from the mausoleum where their iconic leader is buried. To mark the anniversary, Palestinians in the West Bank are holding a series of events, including film screenings, to celebrate the life of a man remembered by many as a passionate proponent of Palestinian rights who led his people through nearly four decades of armed struggle and peace negotiations. But the Gaza-based Palestinian Centre for Human Rights said Hamas officials had ruled out any anniversary events, citing violence that marred a 2007 rally, when Hamas forces opened fire, killing seven. Fatah condemned the ban, with spokesman Ahmed al-Assad saying the shameful act punishes not only the Fatah movement in Gaza but the entire Palestinian people. Fatah sources in Gaza told AFP Hamas forces broke up a private commemoration event inside the offices of a Fatah member. The Foreign Press Association, which represents foreign reporters in Israel and the Palestinian territories, accused Hamas of harassing and intimidating journalists trying to cover an Arafat memorial in the southern Gaza city of Rafah. International television crews were detained and ordered to turn over news footage to the authorities, the group said, calling a news blackout on the event unacceptable.