US President George Bush signed off with a defiant farewell over his refusal to accept global climate change targets at his last G8 summit. As he prepared to fly out from his final G8 summit in Japan, he told his fellow leaders: "Goodbye from the world's biggest polluter.' President Bush made the private joke in the summit's closing session, senior sources said yesterday. His remarks were taken as a two-fingered salute from the President from Texas who is wedded to the oil industry. He had given some ground at the summit by saying he would "seriously consider' a 50 per cent cut in carbon emissions by 2050. But green groups had protested that the summit was a missed opportunity to secure the radical reductions in carbon emissions that were needed to reduce global warming. China and India, who were among the emerging economies invited to attend the G8, refused to sign up to binding agreements without firmer commitments from the US and the other industrialised nations to cut their CO2 emissions. However, there was progress towards a deal on the world trade talks in Geneva. On the final day of their three-day summit, the G8 countries agreed to instruct their negotiators to make every effort to secure a deal when talks resume on 21 July. Although a similar call by the G8 summit two years ago failed to break the deadlock in the seven-year trade talks, officials are more confident that this month's negotiations will be successful. They say there is a growing recognition that it will be much harder to secure a deal after a new US President takes office next January because of pressures to protect American farmers during this year's election campaign