The University and College Union is planning fresh strikes against any institution that refuses to publicly call for talks on pensions, in a bid to expose hard-line vice-chancellors.
The UCU has told its branches that it plans a one-day stoppage in late May over employer-driven changes to the £30 billion Universities Superannuation Scheme.
But institutions "will be offered dispensation from the strike if they write publicly to the Employers Pension Forum (EPF), Universities UK and the USS to call for meaningful and time-limited talks to resolve the dispute", according to a circular letter from Michael MacNeil, the union's head of higher education.
Under the current plans, the changes to the scheme include linking pension increases to a lower rate of inflation and ending final-salary pensions for new members.
In a separate development, the USS announced this week that it would postpone the next meeting of the Joint Negotiating Committee (JNC) to allow the UCU to discuss alternative plans with the employers. The meeting - scheduled for 14 April - will now be held on 10 May.
Last week, the USS threatened to take High Court action against the union's five pension negotiators and to make them individually liable for costs.
The five - four of whom are serving or retired academics - have repeatedly refused to attend meetings of the scheme's decision-making committee in an effort to block the changes. The USS has called their stance "intolerable". Without the UCU representatives, the committee cannot be quorate and the changes cannot be finally approved.
The union's representatives believe that if they attend, the committee's independent chair, Sir Andrew Cubie, will use his casting vote to back the employers - as he did last year when two years of talks on reform of the scheme reached a stalemate. But in a statement issued by the USS, Sir Andrew says that "no one should presume to know how I might exercise my vote".
In his letter to the branches, Mr MacNeil says it is "vitally important that the UCU does not let the employers continue to hide behind the actions of the USS board. Our strategy needs to focus on and place pressure on individual employers to call for talks."
He adds that failure to resolve the dispute will lead to another one-day strike in June, "which will allow us to target exam administration".
A USS spokesman said the trustee board would ask the JNC to formally decide on proposals for changes to the scheme at the 10 May meeting. "And in the intervening period, the UCU will have this further opportunity to produce its own alternative proposals and invite the employer representatives to respond to them," he said.
An EPF spokesman said the group hoped to receive the UCU's revised proposals "well in advance of the rescheduled JNC meeting" and urged the union to "re-engage with the long-established process for agreeing changes to the USS and attend the 10 May meeting".