A left-wing ‘ super-union ’ with almost 1.8million members could be created by a controversial merger of Labour ’ s biggest donor Unite and the biggest civil service union after the election , senior Conservatives fear . They warn that a merger between the Public and Commercial Services Union ( PCS ) and the Unite union would threaten the impartiality of Whitehall . Half of all civil servants are members of the PCS , which is not currently politically affiliated . If the two unions merged , they would effectively be subsumed into a union which is Labour ’ s biggest financial supporter . Unite , which has donated millions to Labour since Ed Miliband became leader of the party , could be set to merge with the Public and Commercial Services Union . Unite is at least five times larger than PCS , which claims a membership of 270,000 . Unite , which has made £14.3million in donations to Labour since Ed Miliband became leader in 2010 , has 1.42million members . A Conservative source said : ‘ A takeover of PCS by Labour ’ s biggest donor , Unite , would make over half of all civil servants members of a Labour-affiliated union . ‘ PCS and Unite must come clean about their secret plans . No takeover can be permitted to imperil the perceived impartiality of the civil service. ’ The PCS has been in financial difficulty following cuts to the civil service , as well as an end to a system where Government departments automatically deducted union dues from the payroll . A leaked document suggests it plans to sell its headquarters to a private equity fund and suspend national elections for this year . The union blames its financial crisis on the downsizing of the civil service , now a fifth smaller than it was in 2010 . The end of the ‘ check off system ’ , which saw union fees deducted automatically from salaries by many Government departments has also squeezed the PCS . MPs have warned a left-wing merger between the PCS and Unite ( Unite protest pictured ) would threaten the impartiality of Whitehall . Cabinet Office minister Francis Maude has overseen the closure of this scheme at the Home Office , Department for Work and Pensions , HMRC , the Ministry of Justice and the Ministry of Defence . In addition , the Government has clamped down on so-called ‘ facility time ’ , whereby union officials are paid by the taxpayer to work for a union . The overall cost of such taxpayer-subsidised union officials has fallen by more than two-thirds , while the number of full-time union officials paid for by the public purse has fallen from over 200 to fewer than ten . Last year , the PCS discussed the possibility of a merger with Unite at its annual conference , but the idea was shelved . A source at the PCS played down the prospect of the deal with Unite being revived , saying : ‘ It ’ s no secret that we had informal discussions . These proposals were never driven by finances . Our conference voted against a motion from the national executive saying we should carry on exploring it , and said we should set more formal conditions . So it ’ s not on the horizon. ’ Unite ’ s general secretary Len McCluskey suggested last year there would be ‘ no further progress ’ on merger talks with the PCS unless it changed its membership rules . Hinting at the reasons for the breakdown of talks , he told delegates ‘ our rules don ’ t change , our structures don ’ t change ’ . PCS members apparently insisted they would not back a new relationship with Unite if their union membership fees contributed to Labour Party coffers .
Merger of Unite and PCS unions could threaten impartiality of MPs . Whitehall warn it would make half of all civil servants members of 'super-union ' Unite has donated £14.3million to Labour since Ed Miliband became leader .