By Christoph Steitz and Nina Chestney FRANKFURT/LONDON (Reuters) -Russia delivered less gas to Europe on Wednesday in a further escalation of an energy stand-off between Moscow and the European Union that will make it harder, and costlier, for the bloc to fill up storage ahead of the winter heating season. The cut in supplies, flagged by Gazprom earlier this week, has reduced the capacity of Nord Stream 1 pipeline – the major delivery route to Europe for Russian gas – to a mere fifth of its total capacity. Nord Stream 1 accounts for around a third of all Russian gas exports to Europe. On Tuesd…