LAGOS/LONDON, Oct 18 (Reuters) - European countries and gas traders are reeling from the latest LNG supply shock - a force majeure from Nigeria LNG - that threatens nearly 4% of global supply and further squeezes the continent's resources in absence of Russian pipeline gas. Nigeria LNG declared force majeure this week due to heavy flooding in that it said impacted virtually all of its gas suppliers. NLNG, with 22 million tonnes per year of capacity, said it is working to mitigate the impact, but flood waters are still rising. Unplanned disruptions in the United States, Nigeria and Australia have forced traders to pay millions in inflated costs for alternative supplies. France's Total, the second-largest offtaker, takes around 3 million tonnes per year.

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