(ANSA-AFP) - BUDAPEST, APRIL 24 - Hungary signed Friday a China-financed loan agreement for a high-speed railway linking Budapest and Belgrade, billed as Hungary's biggest ever infrastructure investment and one whose contract details could be kept secret for a decade. "An important agreement was reached today: the construction work can begin with the signing of the loan agreement for the Budapest-Belgrade railway line," said Finance Minister Mihaly Varga in a Facebook video. The 350-kilometre-long (220 mile) high-speed rail line would form part of a planned railway connection linking central Europe with the Chinese-run Piraeus port in Greece. The project is part of China's ambitious "Belt and Road" initiative, Chinese President Xi Jinping's signature global infrastructure project to deliver Chinese goods from east to west. (ANSA-AFP). (ANSA).