Last checked at 
* Hostage toll to rise from provisional 23 - minister
* France cautions against criticising Algerian response
* We must recognise Algeria's help, Cameron says
* Military clearing plant of mines after "final assault"
By Lamine Chikhi and Abdelaziz Boumzar
ALGIERS/IN AMENAS, Algeria, Jan 20 (Reuters) - Algeria saidon Sunday it expected heavy hostage casualties after its troopsended a desert siege, but Western governments warned againstcriticising tactics used by their vital ally in the strugglewith Islamists across the Sahara.
An Algerian minister acknowledged the death toll would rise,and a private television station reported that 25 bodies hadbeen found at the gas plant near the town of In Amenas afterforces staged a final assault against the Islamisthostage-takers on Saturday.
Some Western governments had expressed frustration at notbeing informed of the Algerian authorities' plans to storm thecomplex. But France, which is fighting Islamist rebels acrossthe desert in Mali, joined Britain in playing down anysuggestion the response from Algeria - the main military powerin the Sahara region - had been over-hasty or heavy-handed.
"What everyone needs to know is that these terrorists whoattacked this gas plant are killers who pillage, rape, plunderand kill. The situation was unbearable," French Foreign MinisterLaurent Fabius said.
"It's easy to say that this or that should have been done.The Algerian authorities took a decision and the toll is veryhigh but I am a bit bothered ... when the impression is giventhat the Algerians are open to question. They had to deal withterrorists," he told Europe 1 radio in an interview.
The Islamists' pre-dawn attack on Wednesday has testedAlgeria's relations with the outside world, exposed thevulnerability of multinational oil operations in the Sahara andpushed Islamist radicalism in northern Africa to centre stage.
Algeria, scarred by a civil war with Islamist insurgents inthe 1990s which claimed 200,000 lives, had insisted there wouldbe no negotiation in the face of terrorism.
Prime Minister David Cameron pointed out on Sunday itsrecord in fighting Islamists. "Of course people will askquestions about the Algerian response to these events, but Iwould just say that the responsibility for these deaths liessquarely with the terrorists who launched this vicious andcowardly attack," he said in a television statement.
"We should recognise all that the Algerians have done towork with us and to help and coordinate with us. I'd like tothank them for that. We should also recognise that the Algerianstoo have seen lives lost among their soldiers."
France especially needs close cooperation from Algeria tohave a chance of crushing Islamist rebels in northern Mali. Algiers has promised to shut its porous 1,000-km border withMali to prevent al Qaeda-linked insurgents simply melting awayinto its empty desert expanses and rugged mountains.
Algeria's permission for France to use its airspace,confirmed by Fabius last week, also makes it much easier toestablish direct supply lines for its troops which are trying tostop the Islamist rebels from taking the whole of Mali.
HIGHER DEATH TOLL
Algeria's Interior Ministry had reported on Saturday that 23 hostages and 32 militants were killed during the assaultslaunched by Algerian special forces to end the crisis, with 107foreign hostages and 685 Algerian hostages freed.
However, Minister of Communication Mohamed Said said thiswould rise when final numbers were issued in the next few hours."I am afraid unfortunately to say that the death toll will goup," Said was quoted as saying by the official APS news agency.
Details are only slowly emerging on what happened during the siege, which marked a serious escalation of unrest innorthwestern Africa.
Private Algerian television station Ennahar said on Sundaythat 25 bodies had been discovered at the Tiguentourine plant,adding that the operation to clear the base would last 48 hours.
The bodies were believed to belong to hostages executed bythe militants, said Ennahar TV, which is known to have goodsources within Algerian security.
In London, Cameron said three British nationals had beenconfirmed killed, while a further three Britons plus a Britishresident were also believed to be dead.
One Briton had already was confirmed killed when the gunmenseized the hostages at the plant near the Libyan border, run byNorway's Statoil along with Britain's BP andAlgeria's state oil company.
MULTINATIONAL HOSTAGE-TAKERS
Said reported that the militants had six differentnationalities and the operation to clear the plant of mines laidby the hostage-takers was still under way.
Believed to be among the 32 dead militants was their leader,Abdul Rahman al-Nigeri, a Nigerien close to al Qaeda-linkedcommander Mokhtar Belmokhtar, presumed mastermind of the raid.
One American has also been confirmed dead. Statoil said fiveof its workers, all Norwegian nationals, were still missing.Japanese and American workers are also unaccounted for.
On Saturday President Barack Obama said the United Stateswas seeking a "fuller understanding" from Algerian authoritiesof what had happened, but added that "the blame for this tragedyrests with the terrorists who carried it out".
BP's chief executive Bob Dudley said on Saturday four of its18 workers at the site were missing. The remaining 14 were safe.
The militant attack was one of the most audacious in recentyears and almost certainly planned before French troops launchedthe operation in Mali this month to stem an advance by Islamistfighters.
Hundreds of hostages escaped on Thursday when the armylaunched a rescue operation, but many hostages were killed.
Before the Interior Ministry released its provisional deathtoll, an Algerian security source said eight Algerians and atleast seven foreigners were among the victims, including twoJapanese, two Britons and a French national.
The U.S. State Department said on Friday one American,Frederick Buttaccio, had died but gave no further details.
Mauritanian news agencies identified the field commander ofthe group that attacked the plant as Nigeri, a fighter from oneof the Arab tribes in Niger who had joined the Algerian SalafistGroup for Preaching and Combat (GSPC) in early-2005.
That group eventually joined up with al Qaeda to become AlQaeda in the Islamic Maghreb (AQIM). It and allied groups arethe targets of the French military operation in Mali.
The news agencies described him as "one of the closestpeople" to Belmokhtar, who fought in Afghanistan and then inAlgeria's civil war of the 1990s. Nigeri was known as a man for"difficult missions", having carried out attacks in Mauritania,Mali and Niger.
The apparent ease with which the fighters swooped in fromthe dunes to take control of an important energy facility, whichproduces some 10 percent of the natural gas on which Algeriadepends for its export income, has raised questions over thecountry's outwardly tough security measures.
Algerian officials said the attackers may have had insidehelp from among the hundreds of Algerians employed at the site.
Security in the half-dozen countries around the Saharadesert has long been a preoccupation of the West. Smugglers andmilitants have earned millions in ransom from kidnappings.
The most powerful Islamist groups operating in the Saharawere severely weakened by Algeria's secularist military in thecivil war in the 1990s. But in the past two years the regionalwing of al Qaeda gained fighters and arms as a result of thecivil war in Libya, when arsenals were looted from MuammarGaddafi's army.
