As Papernet reported last week, the Finnish white-collar workers' union Pro launched a strike threat at all UPM mills in Finland, if an agreement between the Finnish Forest Industries Federation and Pro has not been reached until April 6.The negotiations between the parties ended Monday evening, without result. No further negotiations are planned at the moment, and the strike is consequently likely to start tomorrow, Wednesday.The background to the conflict is that the discussions between Pro and The Forest Industries Federation regarding this year's salary increases have stalled. Pro claims a 3.5 percent increase, which is rejected by the Forest Industries Federation.The strike will concern approximately 1,000 white-collar workers at UPM units in Finland.