LISBON, Portugal — A trade union representing inspectors at Portugal’s immigration service says a strike planned for Thursday and Friday is going ahead after the government gave no response to its demands for more staff and resources.

The 48-hour walkout is expected to cause lengthy waiting lines at airport passport controls, though the inspectors are required by law to provide about 30 percent of their normal staffing during the strike.

The union’s national secretary, Marco do Carmo, said Tuesday the labor group has not been in touch with government officials since tabling its demands. The union wants the government to hire 200 more inspectors and renew the department’s computer systems to ensure security and swift procedures.

The government has said it is increasing staff levels and wants to improve work-time flexibility.