As a new round of UN climate change talks began in Barcelona this?Monday, climate activists gathered in the Spanish city to ring 1,000 alarm clocks in front of the conference venue to remind delegates that time is "running out" for a deal.

Ben Margolis, an organizer of the TickTickTick campaign, said: "We will deliver these tick ticking clocks to delegates here for the negotiations to remind them that time is running out for a deal to be made."

He said that in Bali two years ago, all of the governments were committed to reaching a binding agreement in Copenhagen.

"We are telling them that it must be achieved and time is running out for that agreement," Margolis said.

Two hundred activists stood outside the conference venue holding their clocks high and shouting: "Tick tick tick, we need common action quick!"

The activists turned the time on some of the clocks to 3:50, for the reason that 350 ppm (part per million) is the safe upper limit for carbon dioxide in the atmosphere according to some scientists.

Margolis said he would try to find an opportunity to personally deliver one of the alarm clocks to Yvo de Boer, executive secretary of United Nations Framework Convention on Climate Change.

The UN climate chief said the "clock almost ticks down to zero" in his opening speech at the Barcelona talks.

About 4,000 negotiators and observers have gathered in Barcelona for the last round of the UN climate talks this year before December's Copenhagen conference in which a new agreement on climate change is expected to be made to replace the Kyoto Protocol which will expires in 2012.