WWF, Friends of the Earth and Russia's Sakhalin Environment Watch are among the groups who have written to the credit agencies, claiming that violations of bank lending policies are continuing and urging them to "protect the integrity [of] your bank's commitment to social and environmental responsibility by declining financing".
"Financing of the enormously risky Sakhalin-2 fundamentally conflicts with the department's environmental policies and carries significant risks to your reputation," the statement argues.
Sakhalin Environment Watch says that natural fish stocks in the area have been depleted as a result of the project - and further argues that Gazprom, Shell and its Japanese partners have a "lacklustre approach to the critically endangered western grey whale".
The whale spawns in the area surrounding the gas field.
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