 In 655, he was made "Zhongshu Ling" (中書令), the head of the legislative bureau and still a chancellor post.In 656, Cui, who had been given an additional post as a staff member of Emperor Gaozong's son and crown prince Li Hong as well, offered to resign on account of illness.Emperor Gaozong gave him the post as an advisor to Li Hong and no longer let him serve as "Zhongshu Ling", but gave him the designation of "Tong Zhongshu Menxia Sanpin" (同中書門下三品), making him a chancellor "de facto".