LONDON (AFP) - Demonstrators rallied across Europe on Saturday in protest against Israel's deadly assault in the Gaza Strip, calling for an end to the attacks on the Palestinian territory. In London, celebrities and left-wing politicians addressed crowds in central Hyde Park before marching to the Israeli embassy, which has been the scene of rowdy protests since the Jewish state's offensive against the Hamas movement which controls Gaza began on Dec 27. Organisers hoped that 100,000 people would turn out, though an early police estimate said 12,000 attended. Some carried banners reading "Stop the holocaust in Gaza", "Freedom for Palestine", while others waved Palestinian flags. In London's Hyde Park, British actress Lauren Booth, the sister-in-law of Tony Blair, the Middle East Quartet's envoy, told the crowd that his suggestions for a ceasefire would condemn Palestinians to a "slow, agonising death". Others on the Hyde Park speakers' list included musician Brian Eno and campaigner Bianca Jagger. Meanwhile, a peace rally organised by the Board of Deputies of British Jews is scheduled to take place in London on Sunday. Similar demonstrations took place on the streets of other European cities including Athens, Berlin, Budapest, Paris and Sarajevo, capital of part Muslim Bosnia-Hercegovina. Meanwhile, tens of thousands of protesters marched through central Paris and other French cities Saturday to denounce Israeli's offensive in Gaza and express support for the Palestinian cause. Thousands of French men and women of Arabic descent carrying Palestinian banners, amid cries of God is Greatest and "Israel murderer." As the various groups gathered, portraits of slain Hamas chief Sheikh Ahmed Yassin and Lebanese Hezbollah leader Hassan Nasrallah were carried behind those of Latin American revolutionary Che Guevara and Venezuela's President Hugo Chavez. Some 3,800 police were deployed, equipped with riot shields and body armour, but remained discreetly in side streets as the crowd marched on under a sea of Palestinian, Algerian, Turkish, Lebanese and Hezbollah flags. Police and an AFP reporter at the scene estimated the crowd at 30,000, whereas the organisers claimed to have assembled 100,000. "We want to point to the hypocrisy of an international community which votes for tons of resolutions that it never enforces," declared Olivier Besancenot, the leader of France's Revolutionary Communist League. In the northern industrial city of Lille around 10,000 protesters marched, according to both police and organisers, while 3,500 gathered in the Alpine city of Grenoble. Other protests took place in Toulouse in the southwest and Mulhoise in the east. The march came one week after a similar protest in Paris sparked violence when, as the 21,000-strong crowd dispersed and gangs of some 300 rioters looted shops and burned cars in the historic city centre. In western Germany, some 10,000 people according to police, largely from the ethnic Turkish community, protested in Duisburg. Police briefly intervened when some demonstrators threw snowballs at a window bearing two Israeli flags. Police in Berlin said some 6,600 protesters gathered for a peaceful rally in the German capital, with similar rallies of support for the Palestinians in Munich and Cologne. In Athens, more than 2,000 people took part in a protest staged by left-wing organisations and Palestinians, shouting "Freedom for Palestine" before marching on to the Israeli embassy. In Utrecht in the Netherlands some 500 people gathered to remember the Palestinian and Israeli civilians killed in the conflict, organisers IKV Pax Christi said. A Gaza rally is planned for Madrid on Sunday.