The far-right Swedish Democrats winning 17.6 percent - less than predicted by some polls but enough to give them a decisive role in the formation of a new government - "once more sounds the alarm", Republic on the Move (REM) leader Christophe Castaner said in a statement Monday.
"After Austria or Italy, it is Sweden's turn to experience this populist wave which, everywhere in Europe, constitutes a danger for our countries," he warned, calling for a "new progressive, federating project, the only way to answer our collective challenges: development, the migration question, the environment and the climate, and the struggle against terrorism".
"Let's refuse to abandon our common future to the populists and nationalists," Castaner declared. "Let's defend a more united Europe with more solidarity and let's ensure more freedom."
REM will fight for this programme, alongside other "progressive forces", during next year's European elections, the statement concluded.