UK Prime Minister Boris Johnson has made an urgent appeal to world leaders before the <a href="https://www.thenationalnews.com/world/uk-news/2021/10/28/success-or-failure-for-king-of-cop26-boris-johnson-hang-on-carbon-commitments-and-cash/" target="_blank">Cop26 environmental summit, saying the world</a> is facing a “critical moment” from which it might not recover. He was speaking in Rome, Italy, where the <a href="https://www.thenationalnews.com/world/uk-news/2021/10/29/g20-leaders-roman-holiday-a-climate-warm-up-before-cop26/" target="_blank">G20, a body that makes up of the world’s 20 largest economies</a> and accounts for more than 80 per cent of global carbon emissions, is meeting. “If we don't act now it will be too late,” the prime minister's official spokesman said. The Cop26 has been hit with some big-name refusals to attend, including world’s biggest polluter China, Russia — number 4 on the list — and Brazil, home to at-risk rainforests. Mr Johnson is taking a tough message to the G20 that, as they have done the most to cause global warming, they now have to make themselves accountable and help those nations now experiencing the most severe consequences. “Cop26 needs to mark the beginning of the end of climate change,” the spokesman said. “The next few days are a critical moment for world leaders to demonstrate that they can show the climate ambition needed. “The success of Cop26 still hangs in the balance. Too many countries are doing too little. “As the countries with the greatest historic and modern contributions to global warming who have built their economies on the backs of burning fossil fuels, G20 offers the key to unlocking global action and making progress we so badly need to live up to our commitments.” The spokesman added that while G20 nations are overwhelmingly responsible for the problem, poorer nations are reaping the consequences. “Climate-vulnerable countries are increasingly experiencing flooding, wildfires, heatwaves and the prospect of their economies being devastated due to climate change. “On Monday, G20 leaders will come face to face with leaders from those countries at Cop26 and will have to account for their actions.” He said that while more countries were now coming forward with commitments to reach net-zero emissions, more needed to be done if they want to meet the goal set in the Paris Agreement of limiting global temperature increases to 1.5<b>°</b>C. Mr Johnson's spokesman said it was still important to keep making progress, insisting the UK was leading by example with the publication this month of the world's first comprehensive net-zero strategy. He added that if they were to succeed in reaching global net zero by the middle of the century, it would mean they would need to halve emissions by the end of the decade. “What success looks like is ensuring that we have commitments sufficient to keep 1.5 alive,” the spokesman said. “We need actual hard commitments from all countries if this going to be a success. “This is an important moment to use this gathering of world leaders as we come to the final days before Cop to look them in the eye and make sure we are getting the level of action that is required.”