London - Thousands of people from around the world gathered Saturday in London to stage a mass protest demonstration ahead of next week's Group of 20 (G20) summit in the British capital.

Braving cold and rainy weather the demonstrators were marching under the motto "Put People First" in a rally and carrying banners saying "Jobs, Justice and Climate."

More than 150 trade unions, peace activist groups and environmental protection organizations were behind the demo taking place in Hyde Park.

Saturday's demo was the starting signal for what is to be a series of protests in the days leading up the April 1 and 2 summit.

The organizers stressed that the protests were to be peaceful. Brendan Barber of the British trade union confederation TUC, said "If there are other groups who want to cause trouble, I don't want to see them anywhere near our event."

His comment came as meanwhile police were out in force in to prevent violence. (dpa)