London — Leaders of Britain's trade union movement have taken steps to end four years of ''cold war'' with the government of Prime Minister Margaret Thatcher. The breakthrough came at two meetings between a Trades Union Congress (TUC) team led by the general secretary, Len Murray, and Mrs. Thatcher's employment secretary, Norman Tebbit, who is threatening to push through a series of legal curbs on trade union activity.
Mr. Murray emerged from the meetings speaking of Mr. Tebbit's ''willingness to listen,'' writes Monitor contributor Alexander MacLeod. He advised trade union rank and file to allow the TUC-government dialogue to continue and privately warned union activists that any attempt to prolong the ''cold war'' would be counterproductive. But militant unionists immediately let it be known that at next month's TUC annual conference the new Murray line would be contested vigorously.
Mr. Tebbit wants trade unions to hold secret ballots for the election of governing bodies and the calling of strikes. Another provision in his proposal would give workers the right to opt out of trade union ''political funds'' - money provided by unions for Labour Party coffers. Tebbit says many workers are not Labour Party supporters and should not be forced to fund the party's campaigns.