Germany's services union, Verdi, has said it will increase pressure on Germany's postal service, Deutsche Post, by calling for more warning strikes at mail depots, which have hampered delivery throughout the country since Saturday. On Thursday, according to a Verdi spokesperson, some 700 postal employees in several federal states stopped work for short periods of time and 2.2 million pieces of mail remained undelivered. Verdi, which represents 160,000 postal workers, is asking for a four percent pay hike during the current round of wage negotiations. Jürgen Blohm, a spokesman for Deutsche Post, called the demand "unrealistic." But Verdi spokesperson Cornelia Hass told reporters that the union had examined the company's balance sheet and that it is "confident it made the right decision" in asking for the 4 percent increase. Temporary work stoppages by 2,200 employees since Saturday have caused delays for about 7.2 million mail items.