Times Online: London Canada and Japan were blocking a possible deal on climate change at the Copenhagen summit, Sir David King, the former Chief Scientific Adviser, warned yesterday.Speaking at the World Conference of Science Journalists, Sir David said that the two countries had stepped into the breach left by the Bush Administration, which had strongly resisted cutting CO 2 emissions."Copenhagen [the site of upcoming global emission talks this december] is faltering at the moment,” said Sir David. “The Americans are now fully engaged. But several countries are blocking the process."Governments previously were able to hide behind the US’s intransigence on climate change, he said, but the pro-climate policies being launched by the Obama administration means this is no longer possible. “The time has come for people to reveal their cards,” he told delegates.