* Emissions monitoring system starting point for global deal
* IMO energy efficiency plan will not cut CO2 fast enough
(Adds NGO reaction in paras 11, 12)
LONDON/BRUSSELS, Oct 1 (Reuters) - Global steps to reduce greenhouse gas emissions from the shipping industry are moving too slowly so the European Union will introduce its own system next year in a bid to accelerate reform, its executive body said on Monday.
International shipping accounts for around 3 percent of the world's emissions of carbon dioxide, the greenhouse gas widely blamed for global warming, and this share could go to 18 percent by 2050 if regulation is not in place, according to the International Maritime Organisation.
There is currently no international regulation of greenhouse gas emissions from ships. Despite years of efforts in the IMO and the United Nations' climate division, global measures have been limited.
The IMO agreed last year to introduce energy efficiency measures for the design of new ships from 2015, but this measure alone will not be enough to ensure emissions are cut quickly enough, the EU Commission said in a statement.
"Discussions about further global measures are ongoing at IMO level, but we need intermediary steps to quickly deliver emissions reductions, such as energy efficiency measures also for existing ships," it added.
The EU Commission has threatened to enforce its own shipping regulations if the IMO fails to find a global solution, as it has with aviation.
The aviation sector was included in the EU's Emissions Trading System (ETS) from Jan. 1 this year but opposition and threats of retaliation from non-EU airlines have led to a major diplomatic row.
The EU Commission has said it was considering several options to cut shippingemissions, such as a fuel or carbon tax, mandatory emissions reductions per ship or inclusion in the ETS.
A global approach towards setting a system for monitoring, reporting and verification of emissions based on fuel consumption is seen as a starting point towards a globally-agreed market-based solution.
It is "our intention to pursue such a monitoring, reporting and verification system in early 2013...This will help make progress at global level and feed into the IMO process," the Commission said.
However, environmental groups were disappointed by the EU Commission's plan, saying monitoring did not address the main issue of reducing emissions from ships.
"The call for improved energy efficiency for existing ships is a welcome move and efforts should proceed in parallel at the EU and IMO level but should not delay an early decision on an EU market-based measure," said non-governmental organisations Transport & Environment and Seas at Risk in a joint statement.
The IMO's Marine Environment Protection Committee is meeting this week in London, where it will work on technical and operational issues related to energy efficiency measures.
(Reporting by Nina Chestney; editing by Jason Neely and Keiron Henderson)