Berlin, Oct 11 (IANS): Thousands of people protested in Berlin on Saturday against a free trade deal under negotiations between the US and the European Union (EU).

Protesters including civil rights groups, environmentalists, labour union members and political parties marched in streets of downtown Berlin, banging drums, clutching flags and posters and chanting slogans, reported Xinhua.

Police estimated that 100,000 people took part in the demonstration, while the organizers said up to 250,000 went to the streets.

The US and the EU started talks on the deal, known as the Transatlantic Trade and Investment Partnership (TTIP), in 2013. Once completed, it will create the largest free trade zone, covering nearly half of world's gross domestic product (GDP).

Supporters in Europe believed that the deal will boost exports, create jobs, fuel growth and strengthen Europe's voice in world trade rules, while opponents feared that Europe's strict standards on environment and food safety will be eroded, and local governments' regulation power in dispute settling be weakened.

The German government insisted that the deal was in interests of Germany and Europe, benefiting especially German small and medium-sized enterprises which were exports oriented.

In full page advertisements in several German newspapers on Saturday, German Economy Minister Sigmar Gabriel tried to allay the public's fear, saying that by clinching the free trade pact, Europe will have the chance to "set a new global standard for the growing global trade".