(Updates with quotes, protests)
By Alister Doyle Environment Correspondent
BONN, Germany, Nov 11 (Reuters) - U.S. cities, states and businesses accounting for more than half the country's economy remain committed to the 2015 Paris climate accord despite President Donald Trump's plan to pull out, an anti-Trump alliance said on Saturday.
The "America's Pledge" report, presented on the sidelines of 200-nation talks on global warming in Bonn, Germany, said non-federal U.S. backers of the Paris pact accounted for $10.1 trillion or 54 percent of U.S. 2016 gross domestic product.
"The group ... represents a bigger economy than any nation outside the U.S. and China," said former New York mayor Michael Bloomberg, a leading opponent of Trump's decision in June to withdraw from the agreement and to promote U.S. coal and oil.
No other nation has followed Trump's lead. Several hundred people attended the launch of the report in a huge tent pavilion outside the main venue to try to persuade other nations "we are still in" despite Trump.
The study, led by Bloomberg and California Governor Jerry Brown, says it is the first to assess the extent of non-federal support for climate action by U.S. cities, businesses and states.
Some green activists said the plans did not go far enough.
They interrupted a speech by Brown to denounce fracking and oil drilling in California and unfurled a banner showing the California flag, with an oil rig spraying oil onto the grizzly bear it depicts.
"We need to do more," Brown said in response. "We have to get off oil and gas. But we've got to get off coal first. Unfortunately in politics we don't have a magic wand."
The Paris agreement seeks to end the fossil fuel era this century with a radical shift to cleaner energies such as wind and solar power to curb heat waves, downpours, floods and rising sea levels.
Fiji's Prime Minister Frank Bainimarama, presiding at the U.N. talks, praised the anti-Trump alliance. "We are in the same canoe. No one is immune to climate change," he said in a speech to the meeting.
The Trump administration, which will have to wait until 2020 formally to quit the Paris agreement, plans to organise a side event on Monday entitled "fossil fuels and nuclear power in climate mitigation".
The America's Pledge report said that backing the Paris Agreement meant rallying around a target set by former President Barack Obama to cut U.S. emissions by between 26 and 28 percent below 2005 levels by 2025.
It also said 20 U.S. states, 110 U.S. cities and more than 1,400 businesses with U.S. operations representing $25 trillion in market capitalization had already set quantified targets to cut emissions.
Together they accounted for 900 million tonnes of greenhouse gases per year, it said.
And U.S. net greenhouse gas emissions have dropped by 11.5 percent in the past decade, while the economy grew by 15 percent, it said.
Laura Phillips, vice president of sustainability of Wal-Mart Stores Inc said investments to reduce emissions and shift to cleaner energies "have saved us a lot of money".
Ed Markey, a Democratic senator from Massachusetts, said "U.S. Senator President Trump might want to cop out but we know that 'cop' stands for Can't Obstruct Progress (or) Climate Outlasts Presidents." (Reporting by Alister Doyle; Editing by Ros Russell)