Citing the nuclear disaster in Fukushima, environmental activists at a UN meeting Sunday urged bolder steps to tap renewable energy so the world doesn't have to choose between the dangers of nuclear power and the ravages of climate change. The call came at the opening of the six-day meeting in Bangkok aimed at implementing resolutions tabled at the UN Climate Change Conference in Cancun, Mexico, in December, 2010. Senior officials from governments and international organizations will already be playing some catch-up as deadlines - including one for the formation of a multibillion fund to help developing nations obtain clean-energy technology - have been missed along a roadmap leading to another climate summit at the end of the year in Durban, South Africa. Before the Bangkok meeting, the UN's top climate change official warned that a very significant global effort would be required to keep temperatures from rising more than 2 degrees Celsius (3.8 F) above preindustrial levels - an agreement reached in Cancun between 193 countries, most of which are represented in Bangkok. Pledges to reduce emissions made by countries so far equal only 60 percent of what scientists say is required by 2020 to stay below the two-degrees threshold. “We did the easy thing at Cancun and left the difficult ones for Durban. And the politics are getting more difficult this year than last,” said Artur Runge-Metzger, a European Union climate change official, pointing to efforts by Republicans to block some of President Barack Obama's efforts to reduce emissions. “We need to see big strides forward before we get to Durban. We have to speed up the pace of work,” Runge-Metzger said. One of the issues taken up in Bangkok will be the formation of the Green Climate Fund, which is to aid developing nations obtain clean-energy technology. Governments have agreed to mobilize $100 billion a year, starting in 2020, but a “transition committee” to design the fund, which was to have been formed last month, is still being discussed along with exactly how the money will be raised. Technology committees and other institutions to implement resolutions are still on negotiating tables, and it was unclear how much the delegates could accomplish in Bangkok. The World Wide Fund for Nature said the Bangkok talks needed to build on the “fragile compromise” at Cancun and “boost the overall ambition levels of the talks if we are to avert the worst consequences of climate change.” Greenpeace, another non-governmental organization, said that in light of the Japan disaster, governments represented in Bangkok were obliged to speed up changes in their energy sectors and promote green technologies. “The world does not have to choose between climate disasters and disasters caused by dangerous energy like nuclear. We can choose a safe future where our societies are powered by renewable energy,” it said. As the conference began, activists from Asian and African countries began a weeklong protest outside the United Nations building, carrying an effigy of Uncle Sam to symbolize the role of the industrialized world in climate change. They said rich nations owed a huge climate debt to be repaid to developing ones by funding and technology transfer. The global effort to avert climate change began with a 1992 UN treaty, when the world's nations promised to do their best to rein in carbon dioxide and other heat-trapping gases emitted by industry, transportation and agriculture. Progress, however, has been slow and many scientists warn that dramatic reductions in emissions will be needed to substantially slow the melting of the polar ice caps and glaciers, the rise of sea levels and other consequences of global warming.