AFP/Beijing

China on Saturday amended the country's criminal law, tightening corruption sentencing, reclassifying sex with underage prostitutes as rape and eliminating the death penalty for nine crimes, state media reported.

The standing committee of the National People's Congress (NPC) said people convicted on serious corruption charges and who were handed death sentences suspended for two years will have those converted to life in prison after the two-year period, the official Xinhua news agency said.

The change is to "safeguard judicial fairness" and prevent "the most corrupt criminals from serving shorter prison terms through commutation", Xinhua quoted the NPC as saying.

Ruan Qilin, a professor at the China University of Political Science and Law, said that the change to corruption sentencing was aimed at officials who use illegal means to have their sentences commuted or to achieve parole or non-prison sentences, the agency reported.

Chinese President Xi Jinping has launched a much-publicised drive to crack down on corruption, vowing to take on both senior as well as low-level officials.

Critics, however, say there are no safeguards against the campaign being used for political purposes and that no systemic reforms have been introduced to fight graft.

China also repealed the crime of sex with prostitutes who are underage and instead made it rape, a crime subject to harsher punishment, Xinhua said.

Previously under the law, people who had sex with prostitutes aged below 14 years old faced a maximum of 15 years in prison, according to the agency.

It added that those convicted of raping a child may face the death sentence.

Prostitution is illegal in China but an estimated several million sex workers operate from establishments including karaoke bars, hair salons, saunas and massage parlours.

China's public security ministry ordered a nationwide crackdown on the sex trade last year following an expose of a city known for prostitution amid criticism that authorities long turned a blind eye.

The NPC also approved the removal of the death penalty for nine crimes, Xinhua said.

These include smuggling of weapons, ammunition, nuclear materials and counterfeit currency; the counterfeiting of currency; fraudulently raising funds; arranging for a person or forcing a person to carry out prostitution; the obstruction of duty of a police officer; and creating rumours during wartime to to mislead people.

Xinhua said that the maximum penalty for those crimes would become life in prison.