The UCU has mounted a series of rolling strikes at universities in Wales, Scotland, Northern Ireland and England over the past week in response to the employers' plans for cuts to the Universities Superannuation Scheme's benefits.
The USS was created for pre-1992 universities, and UCU members at 63 such institutions have voted for strikes. They were due to culminate in a UK-wide "day of action" on 24 March, to include strikes over the employers' 0.4 per cent pay offer for this year and their refusal to agree a national deal on avoiding redundancies.
Members at post-1992 universities were also due to strike over proposals for higher member contributions and an end to final-salary benefits in the Teachers' Pension Scheme.
There has been no national industrial action in the sector since 2006, when lecturers went on strike over pay.
Alan Carr, the UCU's treasurer and a negotiator on the USS, said of the action: "Hopefully it will bring the employers back to the negotiating table. If it doesn't, we will be taking further, more serious industrial action."
Asked what this would entail, he said: "It would be highly targeted and designed to have the maximum impact on examination and assessment processes."
In a week of posturing by those on opposite sides of the dispute, the union criticised Aberystwyth and Lancaster universities for the "chilling" warnings they had sent to staff.
The universities advised that those who take part in strike action will have their pension contributions suspended for those days, leaving them ineligible for death-in-service benefits.
Employers and mission groups were united in criticising the strikes as disruptive to students.
Wendy Piatt, director general of the Russell Group of large research-intensive institutions, said the USS changes were "moderate" in comparison with other schemes' reforms.
Paul Marshall, chief executive of the 1994 Group of smaller research-intensive institutions, described the 4 per cent pay claim submitted by the UCU and other unions as "way beyond" what could be expected in a "difficult economic climate".