UPDATE 1-Sudan shuts separatist newspaper - state media

* Anti-south paper suspended "indefinitely"-state media

* Papers warned of return of daily censorship (Adds detail, background, return of censorship)

By Andrew Heavens

KHARTOUM, July 6 (Reuters) - Sudan closed a newspaper campaigning for the separation of the country's north and south, state media reported on Tuesday, signalling a new crackdown before a vote on southern independence.

Al Intibaha, was "suspended indefinitely" because of the way it strengthened separatist tendencies, said The Sudanese Media Centre, a news outlet with links to state security.

Other newspapers said articles about conflicts in the south had also been blocked, and national security officers had warned them they would resume daily censorship of publications.

Southerners are six months away from a referendum on whether they should split away as an independent nation.

Analysts say most southerners favour independence but President Omar Hassan al-Bashir, leader of the main party in the north, has promised to campaign to persuade southerners to vote for unity.

The referendum was promised in a 2005 peace deal that ended more than two decades of civil war between Sudan's Muslim north and the south, where most follow Christianity and traditional beliefs.