* 12-hour halt to drilling after second Greenpeace protest
* Greenpeace calls on Greenland to show spill response plan (Adds date of ruling)
LONDON, June 6 (Reuters) - Cairn Energy (CNE.L) said it was drilling in Greenland again after a 12-hour stoppage as environmental protesters were removed from its exploration vessel.
The oil and gas explorer said it resumed drilling after Greenland authorities removed 18 Greenpeace activists who had boarded the Leiv Eiriksson vessel on Saturday. [ID:nLDE75305E]
The incident off the west coast of Greenland was the second time Greenpeace protesters, who object to oil exploration in the Arctic, have boarded the drilling vessel this year.
Cairn is leading a charge into offshore Greenland, which explorers believe could hold billions of barrels of oil.
The dispute between the two parties appeared to be heating up after Greenpeace said on Sunday it lodged a complaint with Greenland's parliament calling for the release of an oil spill response plan.
Last week, Cairn filed a lawsuit against Greenpeace to deter it from disrupting exploration plans in the Arctic, one of the last untapped hydrocarbon basins in the world. [ID:nLDE7511T6]
A Greenpeace spokesman told Reuters the ruling will be announced on Wednesday afternoon. Cairn is seeking fines of up to 2 million euros ($2.9 million) for every day protesters stop it drilling. (Reporting by Sarah Young and Ivana Sekularac; Editing by Paul Hoskins and Dan Lalor)