* Maliki issues final warning

* Iraqi forces in Amara for crackdown on Shi'ite militias

* Bush expects long term security pact with Iraq

By Haider al-Nasrallah

AMARA, Iraq, June 14 (Reuters) - Iraq has sent army and police units to the southern city of Amara for a new crackdown on Shi'ite militias, local officials said on Saturday.

The operation is the latest stage in Prime Minister Nuri al-Maliki's drive to stamp his government's authority on areas of the country previously controlled by Shi'ite militias or Sunni Arab insurgents.

In a statement read on al-Iraqiya television, Maliki said outlaws and criminals were being given their "last chance" to surrender and hand over heavy and medium weapons and bombs in the next four days.

Iraqi tanks were on major streets, security forces patrolled and many checkpoints were set up in Amara, a city of about 250,000 people 300 km (180 miles) southeast of Baghdad which is the capital of Maysan province.

Helicopters dropped leaflets urging residents to stay at home and not to interfere with the operations.

The city is a stronghold of anti-American Shi'ite cleric Moqtada al-Sadr, who agreed to a ceasefire after U.S.-backed Iraqi forces launched a major crackdown on his Mehdi Army militia in Basra in March.

"The decision to undertake the operation has been taken, but the zero hour has not been set yet," Adel al-Muhoudir, governor of Maysan province, told Reuters.

A security official said the operation would target armed groups and some members of the Mehdi Army.

U.S. forces are gradually handing over more security responsibilities to Iraqi forces.

But Iraqi officials say American forces are still needed in the country, which has witnessed sectarian bloodshed, a Sunni Arab insurgency and al Qaeda bombing campaigns since the U.S. invasion to topple Saddam Hussein in 2003.

U.S.-IRAQ PACT

U.S. President George W. Bush said on Saturday that he expected to reach a long-term security pact with Iraq, despite Maliki's description of talks on extending the U.S. troop presence as deadlocked.

"If I were a betting man, we'll reach an agreement with the Iraqis," Bush told a news conference in Paris. "Of course we're there at their invitation."

Maliki has improved his standing with crackdowns on the Medhi Army. Iraqi forces took control of Sadr's Baghdad stronghold after a truce was reached with the cleric.

U.S. and Iraqi military officials say al Qaeda is on the run and that its network has been broken in its last Iraqi urban stronghold, the northern city of Mosul.

Violence has fallen to its lowest level in more than four years. But officials say the security gains are reversible, and Maliki is under pressure at home and abroad to show he can provide Iraqis with sustained security.

In his statement, the prime minister said he had authorised Iraqi security forces to conduct major operations to make arrests and seize weapons in Maysan province from June 19.

"We have to put an end to the chaos of arming (in the province) and crime," he said.

"Because this province and its people suffer from a lack of services and still live in instability because of the attempt of the outlaws and criminals to impose their authority."

Iraqis who give beneficial information about locations of illegal weapons and their owners and outlaws would receive financial rewards, said Maliki.

Iraqi armoured vehicles had arrived from the southern city of Basra and police units had come to Amara from Baghdad and elsewhere, the security official said.

"Army and police have fanned out all over the city in a way we didn't witness before, on the main streets, roads and bridges," said local resident Muhsin Abdul-Hassan.

Sadr ordered a delegation of clerics to go to Amara for talks with regional officials on how the operation would be carried out, said Sayyid Kareem al-Battat, a delegation member.

Battat said the delegation carried instructions from Sadr for Mehdi Army members to respect the ceasefire ordered by the cleric.

He said the provincial governor had promised security forces would respect human rights and that a committee of tribal leaders would supervise the operation.

"We have no objection to implementing the law and arresting wanted people. We don't think that the operation is directed at Sadr partisans because we are all brothers in the city," Battat said. (Additional reporting by Khalid al-Ansary and Aws Qusay in Baghdad and Matt Spetalnick and Jeremy Pelofsky in Paris; Writing by Adrian Croft; Editing by Michael Georgy and Andrew Roche)

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