Mr Simpson, a former Communist, said on Saturday that union members had voted for a change because they felt their leaders were "autocratic and had lost touch with them".

BBC: Tony Blair, left, Derek Simpson, and Ken Jackson, right

European leaders, as well as some American politicians, have repeatedly requested that Ukraine address the situation with Tymoshenko and her allies, who, as leaders of the opposition, threatened the unpopular autocratic administration of Yanukovych, and, the West believed, were victims of political persecution.

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At other times he appeared to delight in petty conflicts with city leaders, who called him high-handed and autocratic.

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