Stellantis NYSE:STLA fell about 1.7% Monday after extending the summer production halt at its Mirafiori plant in Turin by 1 week, Reuters reported.

The automaker told unions the plant will stop operations from July 27 to July 31, ahead of a planned 3-week August shutdown. Stellantis said parts shortages, including engines, bumpers and sensors, have disrupted output as suppliers struggled to keep up with production of the hybrid Fiat 500 launched late last year.

The shutdown also raised demand concerns. Trade union FIM Cisl said repeated stoppages suggest market demand for the Fiat 500 may be weaker than expected. The plant is set to restart Tuesday after a separate week-long closure tied to a local public holiday.

Stellantis aims to produce about 100,000 hybrid and electric Fiat 500 models in 2026, though Europe chief Emanuele Cappellano did not reaffirm that target last month. FIM Cisl also said daily assembly was cut to 400 vehicles from 430 earlier this year.