Top nuclear envoys from North and South Korea will hold bilateral talks on Wednesday in Beijing, South Korea's Yonhap news agency said on Sunday. "The South and the North agreed to set a date for the nuclear talks on September 21," Yonhap quoted a senior Seoul government official as saying. "The exact time and frequency will be discussed there (in Beijing)." South Korean media have reported Wi Sung-lac, South Korea's chief nuclear negotiator, and his North Korean counterpart Ri Yong-ho were already in the Chinese capital to prepare for what would be their second meeting in two months, according to a report of Reuters.