BEIJING (Reuters) - China's ruling Communist Party has issued new rules to push its fight against deeply entrenched corruption, telling senior officials to travel "without pomp", not to have too many staff and not take too many holidays.

President Xi Jinping has waged war against graft since assuming office four years ago, warning, like others before him, that the problem is so severe it could affect the party's grip on power.

The party has already cracked down on what it terms extravagance, hedonism and bureaucratism. The new rules, issued late on Wednesday (Nov 30), further formalise practices and guidelines already generally in effect.

Top officials should "travel without pomp, minimise impact on public life, and not have vehicles exceeding the set standards" say the rules, which were released by the official Xinhua news agency.

Holidays should be limited and properly approved, the"right" number of staff employed, relatives and employees"strictly constrained" and top officials should not delay leaving their offices upon retirement, the rules state.

The Politburo, one of the party's elite ruling bodies headed by Mr Xi, would be the first to follow the rules, and mr Xi himself is leading by example, Xinhua said.

"To forge an iron, one must be strong oneself," it said. "Whatever you demand others do, you should first do yourself; whatever you forbid others to do, you should firmly forbid to yourself," it said.

Government departments should now draft detailed plans to implement the new rules and strengthen supervision, which should be implemented without compromise, it said.

China does not have an independent anti-corruption body and insists the party and the government can police themselves.

Mr Xi's crackdown on corruption has moved in recent months away from high-profile officials to weeding out daily corruption at the grassroots, making almost anyone a potential target.

The drive for a clean party, referred to in official documents as "intra-party supervision", was the focus of a four-day meeting of senior party officials in Beijing in October, which concluded by anointing Mr Xi as "core" leader of the party.

On Wednesday, the party also adopted measures on what it refers to as "democratic life" to ensure officials have the"correct political consciousness".

"The authorities should organise 2016 annual democratic life meetings to analyse party members' integrity by criteria such as loyalty, honesty, frugality and whether they insist on seeking truth from facts," Xinhua said.