PARIS — A long-simmering dispute between unions representing employees of Thales Alenia Space’s French satellite-production sites escalated the week of April 2 with demonstrators occupying offices and demanding immediate negotiations on 2010 salaries.

The demonstrators, representing half a dozen different unions, staged sit-ins but did no damage to property. Work on satellite antennas and subsystems in Toulouse, and at the Cannes satellite-integration plant, continued without interruption, company officials said.

Thales Alenia Space Chief Executive Reynald Seznec, who has not met with the demonstrators up to now, agreed to a meeting on April 8, officials said. Thales Alenia Space, whose French sites produce satellite payload electronics and platforms, has said it expects no revenue growth in 2010 compared with 2009.

Peter B. de Selding was the Paris bureau chief for SpaceNews.