SYDNEY, April 17 (Reuters) – An Australian man has been refused bail after being charged with a foreign interference offence for accepting cash from suspected Chinese intelligence agents, with a Sydney court saying his close ties to China made him a flight risk. Magistrate Michael Barko said Alexander Csergo was a "sophisticated, worldly businessperson" who had been on the radar of Australian intelligence for some time before his arrest on Friday. The prosecution had a strong case against Csergo, who had lived in China for decades, Barko said in refusing bail. Csergo is alleged to have arrived back in Australia…