By Guy Faulconbridge LONDON (Reuters) - British Prime Minister Theresa May appointed a senior career diplomat as envoy to the European Union to replace an ambassador who quit with a scathing resignation letter that exposed frustration among officials over her strategy. Tim Barrow, political director of the Foreign and Commonwealth Office and a former ambassador to Moscow, would take up the post next week, May's Downing Street office said, following the abrupt resignation of Ivan Rogers. The selection of Barrow, a 30 year veteran diplomat, could disappoint some Brexit campaigners who would like to see a known eurosceptic in the post, but may reassure Britain's cadre of civil servants that their expertise is still valued.
