University staff in Bristol and Bath will go on strike for three days next month as part of disputes over pensions, pay and working conditions.
Members of the University and College Union (UCU) are due to walk out from 1 December, after voting in favour of industrial action.
General secretary of the UCU, Jo Grady, has warned that further strikes can be expected in 2022 if the row with the employers goes unresolved.
Earlier this month, UCU members backed strike action in two separate disputes, one on pensions and one on pay and working conditions.
University of Bath members will be involved in the pensions strike only, while members from Bristol will be taking action over both pay and pensions.
As well as the three strike days, union members will begin other forms of industrial action from December 1 including strictly working to contract and refusing any additional duties.
A statement on The University of Bristol Students' Union website reads: "It is disappointing that disputes remain ongoing, and that strike action has now been deemed as necessary.
"We recognise the different frustrations currently being experienced within the student body. We know that this is an important subject which will impact students in different ways, and that there may be a divided opinion on it.
"We’re aware that this will affect the university experience of many, and we also respect the right of university staff to pursue industrial action."
The strike in December is set to go on indefinitely for the five months staff have a mandate to take industrial action for, UCU has said.
"Strikes over three consecutive days are set to hit university campuses next month unless employers get round the table and take staff concerns over pension cuts, pay and working conditions seriously," Dr Grady said.
"UCU has repeatedly asked employers to meet with us to try to resolve these disputes. But while we set out pragmatic solutions that could halt widespread disruption to UK campuses, university bosses refuse to revoke unnecessary, swingeing pension cuts or even to negotiate on issues like casualisation and the unbearably high workloads that blight higher education.
"A resolution to this dispute is simple. But if employers remain intent on slashing pensions and exploiting staff who have kept this sector afloat during a pandemic then campuses will face strike action before Christmas, which will escalate into spring with reballots and further industrial action."
The UCU claims that cuts to the Universities Superannuation Scheme (USS) pensions scheme would reduce the guaranteed retirement income of a typical member by 35%.
It has also suggested that pay for university staff fell by 17.6% relative to inflation between 2009 and 2019, and since then employers have made below-inflation offers, with the latest worth 1.5%.
The UCU held a series of walkouts in 2019 and early 2020 over pensions, pay and conditions, which affected universities across the UK. There was also strike action in 2018 amid a row over pensions.
Larissa Kennedy, president of the National Union of Students (NUS), said: "With vice chancellors' average total pay packets rising to £269,000 per year, it's clear employers can afford to resolve their dispute with UCU over staff pay, which has fallen by an average of 20% in real terms since 2009.
"Staff teaching conditions are student learning conditions, and we mustn't forget many postgraduate students on casualised teaching contracts will be striking.
"The onus for minimising disruption for students lies with university bosses: they must come back to the table to address the clear issues in how higher education is currently run."