The fight against corruption never ends and the zero tolerance to corruption will never change, Chinese president Xi Jinping said in a written interview with the Wall Street Journal published on Tuesday.

"Cracking down on corruption is what all countries must do and what their peoples wish to see. The ultimate purpose of the Chinese Communist Party is to serve the people wholeheartedly," Xi said in the interview ahead of his U.S. visit.

He left Beijing Tuesday afternoon for the state visit at the invitation of U.S. President Barack Obama.

"Our Party owes its governing status to the support of the people, so we must maintain its flesh-and-blood ties with the people," Xi said.

The Party does not operate in a vacuum, so it has unavoidably found itself with problems of one kind or another, Xi said, adding that corruption is just such a persistent one.

The Party must be courageous enough to face up to the problem and go out to correct it through self-purification and self-rectification, Xi said.

"Our people hate corruption more than anything else and we must act to allay their concerns. Therefore, we decided to go after both 'tigers and flies', wrongdoers regardless of their ranks."

Since the 18th Party Congress, China has intensified anti-corruption efforts, dealt with a large number of corrupt officials in accordance with law, including some who used to hold very high offices, and won extensive support and thumbs-up from the Chinese people.

"On institutional building in this respect, let me share with you two remarks I made. The first is that we must keep power in the cage of systemic checks. The other one is, transparency is the best precaution against corruption," Xi said.

As we go further in anti-corruption campaign, we will focus more on institutional building so that officials will not dare and cannot afford to be corrupt and, more importantly, have no desire to take that course, Xi said.

Right now, we are formulating and updating relevant laws and regulations to truly put power inside a more closely-knit cage of effective checks, the president said.

With respect to asset disclosure by officials, China adopted relevant regulations back in 2010 to require such reporting which was subject to random check and verification every year.

Xi said the proportion of verified reporting has increased steadily, and no one would take exception. Should anyone be found to be dishonest, they will be punished accordingly.

"I once said that the fight against corruption never ends. Our zero tolerance to corruption will never change. Nor will our determination, courage and severity with which we punish it in order to rid the Party of corruption."

All acts of corruption must be dealt with, Xi said.

Anti-corruption efforts will not hurt the economy. On the contrary, fighting corruption, including such malpractices as rent-seeking, will help build a clean government, remove hurdles that impede market operations, promote fair rules and bring about a better investment and business environment, Xi said.