Unite leader Len McCluskey has urged Labour to prepare for an early general election because of the strength of public feeling against the austerity measures imposed by the Government.
McCluskey also warned that there will be more industrial action over pay, pensions and cuts to public services.
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Some 465 seats are up for grabs in the lower house, which Abe dissolved last month to call a snap election amid rising approval ratings.
Ministers are also looking at schemes such as “lock-in agreements” to reduce the 250,000 sales that fall through annually.
Staff have racked up hundreds of thousands of dollars in fees as Robert Mueller and House and Senate committees probe Moscow’s meddling.