BEIJING (Reuters) - China aims to speed up the signing of extradition treaties with countries where corruption suspects have fled to, a senior official wrote in state media, as Beijing steps up its overseas hunt for citizens suspected of corruption.

China has been trying to get increased international cooperation to hunt down suspected corrupt officials who have fled overseas since President Xi Jinping began a war against deeply-rooted graft more than three years ago.

But Western countries have been reluctant to help, or sign extradition treaties, not wanting to send people back to a country where rights groups say mistreatment of criminal suspects remains a problem, and also complaining China is unwilling to provide proof of their crimes.

Beijing has vowed to pursue an overseas search dubbed Operation "Fox Hunt" for corrupt officials and business executives, and their assets.

Writing in the latest issue of influential bimonthly Communist Party journal Qiushi, Huang Shuxian, deputy head of the graft-busting Central Commission for Discipline Inspection, said more efforts needed to be made to recover corrupt officials and their assets from overseas.

"Grasp well the important elements of 'people, money and proof'," Huang wrote. "Speed up the signing of extradition treaties and establish law enforcement cooperation with destination countries for those who have fled abroad."

There needs to be a "new international order to fight corruption", with more diplomatic efforts exerted, he added.

At the same time, controls on allowing officials abroad also need to be strengthened, he said.

China last year urged the United States to start talks about an extradition treaty, something the United States has been reluctant to do.

Huang said in April that China faces a tough task in hunting down corruption suspects abroad.

In an indirect admission that China has done a poor job in getting suspects back, Huang wrote that China needed a better understanding of international laws so it had greater "legal tools" at its disposal.

Propaganda efforts needed work too, to win over an international audience. "Strengthen propaganda and public opinion work ... use various platforms to tell China's anti-corruption story well, expound upon China's position and increase our right to speak internationally," Huang wrote.