Officials from the two Germanys began negotiations today on the final phase of unification, and Prime Minister Lothar de Maiziere of East Germany said Berlin should be the new German capital. Meanwhile, in southern Leipzig, farmers said they would dump 2,640 gallons of milk on the streets Monday to protest the loss of business following the economic merger of the German states, the ADN news agency said. Elsewhere, a bomb threat forced the evacuation of East Germany's Parliament while lawmakers were in a session unrelated to the East-West talks. No bomb was found, and the lawmakers returned after about 30 minutes. De Maiziere led the East German delegation in talks today on combining the political systems of the German states. An economic treaty went into effect Sunday that united the German economies. Officials have spoken of all-German elections as early as December. In an interview with ADN, de Maiziere said the pact should give East Germans the same rights as West Germans. He also said the treaty should make Berlin the capital of a united Germany. West German Interior Minister Wolfgang Schaeuble led the West German delegation. Also today, 100,000 metal workers held one-hour ``warning strikes'' to demand higher wages and job protection, said union spokesman Detlef Kuchenbecker. About 10,000 marched through East Berlin to press their demands. Prices have soared in this new free-market society following the economic merger and metal workers have held strikes daily at various plants. East German stores have stocked their shelves with more expensive West German products, forcing up prices. There have also been widespread reports of price gouging by East German stores. De Maiziere and other officials have criticized the price rises. The costs of some foodstuffs varied by 100 percent from one region to another. ``There's no way that can be justified merely by higher transportation costs or overhead,'' de Maiziere told legislators Thursday. ADN reported price rises of 400 percent to 600 percent in northern Mecklenburg and Pomerania regions and said there were long shopping lines in southeastern Dresden. ``There are cities in the GDR (East Germany) where the average price levels are way above those in West Germany,'' said Economics Minister Gerhard Pohl. ``We need certain guarantees that GDR citizens ... won't be exploited.'' Several thousand metalworkers struck at seven plants near Leipzig, where pay talks deadlocked two days ago, according to ADN. The union wants East Germany to adopt the West German system of stipulating salary scales and job descriptions in huge collective contracts by which all the workers in a specific industry are bound. In southwestern Erfurt, 9,000 workers rallied outside their union headquarters as contract talks began, ADN said. The negotiations later collapsed, the agency reported. Workers are demanding that pay levels be brought up to West German standards by next year. The average East German earns less than half the average West German salary. Rents are being kept low to help compensate during the transition from 40 years of socialism to capitalism. But unemployment is expected to surge into the millions as East Germany faces stiff competition from West Germany. East Germany's Communist regime was overthrown last autumn.