College lecturers are to go ahead with two days of strike action next week after talks broke down.
The Educational Institute of Scotland (EIS) had previously suspended planned industrial action to allow negotiations about pay to take place.
EIS said some progress had been made with Colleges Scotland, but no agreement could be reached.
An offer of further talks to take place on Monday was rejected by employers, the union said.
EIS general secretary Larry Flanagan said: “We remain in dispute with employers on the matter of a cost of living pay rise covering the past two years and the year ahead.
“Some additional movement from the employers could deliver an offer that we could put to our members.
“The EIS offered further talks early next week in the hope of progressing discussions, and is extremely disappointed that Colleges Scotland has declined this offer.
“With no improved offer likely to be forthcoming, next week’s two-day strike action will now go ahead.
“The ongoing action short of strike, including a boycott of inputting assessment results into college systems, remains in place.”
Lecturers are demanding what they say is a fair cost of living increase, in line with public sector pay policy.
Strikes have been fixed for Wednesday and Thursday next week.
There have already been four days of such industrial action as a result of the failed negotiations.
The Colleges Scotland Employers’ Association (CSEA) said it has put forward 10 offers trying to reach agreement in the 2017-20 pay dispute.
Heather Stevenson, CSEA interim director of employment services, said: “It’s extremely frustrating that the EIS-FELA has decided to resume their strikes and continue to attack students by withholding assessment results, but colleges are mitigating the impact of their action and we are confident their attempts to cause maximum disruption will not succeed.
“Lecturers in Scotland are by far the best paid in the UK, and the pay harmonisation rises from 2017 to 2020, combined with the improved pay offer on the table from colleges, equate to a national average increase of well over £5,000 - or more than 12%.
“Lecturers have also had significant improvements in terms and conditions over the same 2017-20 pay period, including an enviable 62 days’ holiday per year and a reduction in class contact time to 23 hours per week.
“We believe this significantly improved offer should be taken to their members to decide and will continue engaging with the EIS-FELA to end their industrial action.”