Police in Chang’an district, in the city of Xi’an, announced the training, held at a five-star hotel, after a local television channel reported on rude cops, according to Sangin Daily.

Twenty officers have now been enrolled on the three-month long “style rectification” programme, the force said in a Weibo post.

Local police captain Li Huixian said: “Politeness is something all our officers should possess,” adding that it is “little details” like saluting and smiling that the public appreciate.

But social media users thought the use of a luxury hotel was “ridiculous”.

One Weibo user said: “The problem of poor service can’t be resolved with just a smile.”

Another thought the scheme was just a means of using up excess funds, asking: “Have they not used up their annual budget?”