* AOSIS says some countries "reckless and irresponsible" on climate
* AOSIS calls for 2012 timetable to be agreed in Durban
LONDON, Nov 3 (Reuters) - A group of island states most vulnerable to global warming have lashed out against rich nations for wanting to delay a new international climate pact until years after the Kyoto Protocol on curbing carbon emissions expires in 2012.
The 42-member Alliance of Small Island States (AOSIS) said countries such as Japan and Russia were "reckless and irresponsible" for promoting a delay in the adoption of a new international agreement until 2018 or 2020, just weeks before the start of a United Nations climate summit in Durban, South Africa.
"If we allow this to happen, global warming problems are going to worsen and the impact on a country like Grenada will be devastating," Joseph Gilbert, Grenada's environment minister and current chair of AOSIS, said in a statement.
"We therefore cannot continue to delay making decisions, to 2018 or 2020, as there will not be sufficient time for countries to take action," he said.
If world governments fail to agree a pact that sets tough climate targets then small island countries in the Caribbean, the Pacific, Africa and elsewhere will be further exposed to severe drought, rising sea levels and stronger hurricanes as a result of climate change, Gilbert said.
AOSIS said a large number of developed and developing countries also want a climate deal done before the end of 2012 and are calling for that timetable to be agreed at the climate summit in Durban.
Representatives from more than 190 nations will meet in the South African city from Nov. 28-Dec. 9 to resume climate talks, but a binding pact to reduce emissions looks unlikely to be delivered and may take several years due to deep divisions between rich and poor nations.
The 1997 Kyoto Protocol covers only emissions from rich nations that produce less than a third of mankind's carbon pollution and its first phase is due to expire end-2012. Poorer nations want it extended, while many rich countries say a broader pact is needed to include all big polluters.
Russia, Japan, Canada and others have said they will not sign up to a second commitment period unless it includes all major emitters.
Two years ago, industrialized nations set a 2 degree Celsius warming as the maximum limit to avoid dangerous climate changes including more floods, droughts and rising seas. Some experts say a 1.5 degree limit would be safer.
Scientists have said carbon emissions need to be cut by 80 to 95 percent by 2050 to keep warming levels reasonably safe.
This is well above the collective commitment by developed countries for a 5.2 percent reduction from 1990 levels under the first phase of Kyoto, and well above developed country targets currently on the table.
The AOSIS chair urged developed countries not to renege on their legal commitment and "historical responsibility" to commit to new targets under the Kyoto pact after 2012.
Otherwise, he said: "What this will do is ruin the Kyoto Protocol, wreck the international carbon market, and undermine the credibility of the legally-binding international climate regime that has taken the world more than 20 years to build."
Benchmark U.N.-issued carbon credits <CEREZc1> traded at an all-time low of 6.35 euros ($8.76) earlier on Thursday, before recovering somewhat. ($1 = 0.725 Euros) (Reporting By Jeff Coelho)