BERLIN—Workers at some Amazon warehouses in Germany began strike action on Monday, services sector union Verdi said, as part of a long-running battle with the U.S. tech giant over better pay and working conditions. Germany is Amazon’s biggest market after the United States, and Verdi, a leading services sector union, has been organising strikes on and off at Amazon sites in the country since 2013 to protest low pay and poor conditions. Verdi said it had called the latest strike to demand a rise in pay in line with agreements the union has reached with the broader retail and mail-order industries in Germany. The union said workers at three Amazon warehouses in the states of Saxony and Hesse would go out on strike on Monday, coinciding with All Saints’ Day, which is a public holiday in some German states. It would not say how many workers joined the strike on …