* Last-minute talks seek climate goals for expanded G8
* Rich, poor split on 2050 halving of world emissions
By Alister Doyle, Environment Correspondent
ROME, July 7 (Reuters) - Major economies tried on Tuesday to break the deadlock between rich and poor nations over 2050 goals for cuts in greenhouse gas emissions at a last-minute meeting before an expanded G8 summit in Italy.
Ministers or senior officials from the 17-member Major Economies Forum (MEF) met in Rome to try to agree a declaration for leaders that could be a building block for a new U.N. climate pact due to be agreed in Copenhagen in December.
"We want to prepare in the best way possible the outcome of the G8 and the MEF in view of an ambitious climate change agreement in Copenhagen," said Barbara Helfferich, spokeswoman for European Commissioner Stavros Dimas who was at the meeting.
MEF nations, which account for 80 percent of world emissions, are split over whether to set a target for halving world emissions by 2050, in line with a "vision" adopted by the rich G8 nations at a summit in Japan last year.
China, India and many other developing nations say rich nations are to blame for most emissions from burning greenhouse gases since the Industrial Revolution and must set deep 2020 goals for cutting their own emissions before asking for help.
India, the world’s number four emitter of greenhouse gases, has said it opposes a MEF goal of halving world emissions by 2050, arguing that developing nations need to be able to burn fossil fuels to help escape poverty.
If the deadlock persists, U.S. President Barack Obama, who launched the MEF to pave the way to a U.N. deal, would end the July 9 meeting — part of the G8 summit in L’Aquila, Italy — with just a "chair’s summary" rather than a statement agreed by all 17 MEF leaders.
A June 30 MEF draft said: "We support an aspirational global goal of reducing global emissions by 50 percent by 2050, with developed countries reducing emissions by at least 80 percent by 2050."
The Rome meeting was added after little progress at a MEF meeting in Mexico last month.
Italy, France and Britain on Monday called on major developing nations to sign up for the goal of halving emissions as a way of showing willingness to combat climate change. China has recently overtaken the United States as top world emitter.
A separate climate draft for the G8, dated June 24, indicated progress towards setting a target of limiting a rise in world temperatures to two degrees Celsius (3.6 Fahrenheit) over pre-industrial times.
The European Union views 2C as a threshold for "dangerous" climate changes such as rising sea levels, ever more heatwaves, floods, droughts and extinctions. The United States, Russia, Canada and Japan have not signed up for such a target at the G8.
The G8 draft said "global emissions should peak by 2020 and then be substantially reduced to limit the average increases in global temperature to 2 Celsius (3.6 Fahrenheit) above pre-industrial levels."
Environmental group Greenpeace welcomed the draft.
"At last the G8 is recognising 2C. The wording should have been much stronger, but still: it is in," said Tobias Muenchmeyer of Greenpeace.
Separately, 22 leading climate scientists called in a letter for the summit to set a global peak in emissions by 2020 and a cut of at least 50 percent compared to 1990 levels by 2050.
(Editing by Stephen Brown)