(ANSA-AFP) - SOFIA, OCT 28 - The Bulgarian government and German arms maker Rheinmetall said on Tuesday they have signed an agreement to establish a joint venture to build a gunpowder and artillery shells plant in central Bulgaria. According to the Bulgarian government, the planned factory is one of the largest investments into the country's defence industry, and will contribute to efforts by the EU and NATO to strengthen Europe's defence autonomy. Under the contract signed by the Bulgarian government and Rheinmetall, Bulgaria's state-owned arms maker VMZ and the German firm agreed to construct a plant in the Bulgarian city of Sopot to produce gunpowder, 155-mm artillery shells and modular charge systems. The two companies plan to invest more than one billion euros ($1.2 billion) into the construction the facility, which is expected to be operational within 14 months. (ANSA-AFP).