About a thousand protesters braved the snow flurries and police truncheons here, while activists in New Delhi besieged the U.S. embassy there with phone calls and emails calling for leadership in the UN climate talks. In the corridors of the Bella Centre, where the UN conference is going on, negotiators skirted a sit-in of young people chanting the names of 11 million people calling for a fair ambitious treaty.

It was a day of climate change protests, with voices making themselves heard from around the world.

Outside the Bella Centre, Climate Justice activists led a team of several hundred protesters who pressed against the barricades on Wednesday morning attempting to make their way into the compound. Television pictures showed police using their batons on the crowd, and activists said pepper spray had also been used. Over 200 people were arrested, they said.

Later in the day, organisers announced that an alternative conference venue had been organised for accredited NGO delegates who would not be able to make it into Bella Centre on Thursday and Friday. With heads of state arriving, the number of NGO delegates being allowed in has been reduced from 7,000 to 1,000. About 22,000 NGO delegates have been registered for the summit.

A small group of about 25 youth from across the world resisted security to stage a sit-in at the conference venue itself later in the evening. They spent their time chanting names. "Gu from Iceland, Ajay Kichlu from India, Kabul from Indonesia, Ana S from Ireland..." Canadian student Rhiya Trivedi continued the litany of names. "We are the voice for 11 million people who have signed an online petition for a fair, ambitious and binding treaty," she said. "We are prepared to stay here until we get that treaty or until they remove us forcibly."

In New Delhi, activists from the Climate Satyagraha Camp called the U.S. embassy with messages calling on U.S. President Barack Obama to show leadership at the summit.

"I partied when Obama was elected. But now I feel really disappointed. I am doing this today to make the U.S. realise that their decisions affect my life. It is a crucial time to make my voice heard," said Monika Pandey, a 21-year-old student, speaking from New Delhi. Over 2,000 people also sent emails to the embassy, she said.

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