* No globally-linked C02 market yet
* Calls mount for global carbon price
By Nina Chestney and Alister Doyle
LONDON/BONN, June 2 (Reuters) - A global carbon emissionspricing system pushed by top energy companies is unlikely to bea big part of any United Nations' deal to curb global warming,some experts say, because many countries have little faith insuch cross-border initiatives.
"All countries are relatively sceptical on internationalmarket mechanisms," said Niklas Hoehne, founding partner ofresearch group NewClimate Institute. "They are open to havenational trading mechanisms or national pricing, but to havethese mechanisms internationally, there is a lot of reluctance."
On Monday, BG Group, BP, Eni, RoyalDutch Shell, Statoil and France's Total urged governments to create a global market for carbonemissions, saying this would create a widely accepted price forcarbon and help spur low-carbon investment.
A growing number of investors with trillions of dollars ofassets, along with climate change experts and world leaders suchas German Chancellor Angela Merkel support the plan.
But, wary of the sharp decline in EU carbon pricing, thereis little agreement on specifics. Prices in the EU's EmissionsTrading System, the world's biggest carbon market, have droppedfrom 30 euros a tonne in 2008 to around 7 euros, due to anoversupply of carbon permits and reduced demand after theeconomic slowdown.
"Markets will have a role to play in lowering the cost ofmitigation worldwide ... Exactly how that is going to functionand under what rules and what circumstances remains to bedecided," U.N. climate chief Christiana Figueres said in aninterview at a carbon industry event in Barcelona last week.
KEY APPROACH
The draft of the U.N. deal includes an option to acknowledgethat "carbon pricing is a key approach for cost-effectiveness ofthe cuts in global greenhouse gas emissions," but offers littledetail on how it might work.
The U.N.'s final deal is unlikely to include strong callsfor carbon pricing, said officials meeting in the German city ofBonn this week to prepare for the Paris conference.
Substantive measures to create an international system maybe absent.
The Paris accord may do little more than call on governmentsto nationally implement carbon pricing systems and include amandate to consider rules for international mechanisms, Hoehnesaid.
Around 40 countries already have a price on carbonemissions, covering around 12 percent of annual globalgreenhouse gas emissions, said the World Bank.
Some countries questioned the oil companies' push for carbonpricing.
"They spread a lot of misinformation," said AbdullahiMajeed, environment minister of the Maldives, the Indian Oceanisland nation whose low topography makes it a potential victimof rising sea levels. "This might be an attempt to delay, ratherthan speed up, work on a Paris accord." (Additional reporting by Susanna Twidale; Editing by DavidHolmes and Katharine Houreld)