ANTRIM (Reuters) - The killing of two soldiers by dissident republicans in Northern Ireland will not be allowed to derail the peace process in the British-ruled province, Prime Minister Gordon Brown said on Monday.

British troops would not be put back onto the streets of Northern Ireland, a senior military official said, as leaders tried to ensure that the worst attack in a decade did not reverse progress made since the Good Friday peace deal in 1998.

The IRA, which fought British rule for decades and drew support from the minority Roman Catholic community, and pro-British Protestant guerrilla groups agreed to ceasefires under the 1998 deal.

The agreement helped to greatly reduce sectarian violence, which has killed more than 3,600 people in Northern Ireland since the late 1960s.

Brown on Monday visited the army base in Antrim where gunmen from the Real IRA splinter group killed the two soldiers, who had been due to deploy to Afghanistan. Brown then held talks with Northern Ireland's political leaders in Belfast.

They want to send out the message to the world, as I do, that the political process will not and can never be shaken, Brown said.

FEARS OF BACKLASH

The Real IRA wants an end to British rule and a united Ireland, but is shunned by the province's political leaders.

It carried out the deadliest single bombing of Northern Ireland's sectarian violence in the market town of Omagh in August 1998. Twenty-nine people were killed.

While security experts question how much capability the Real IRA actually has to launch a sustained campaign of violence, there are fears that Saturday's killings could spark a bloody backlash from pro-British guerrilla groups.

This here could kick it off again, said John Stevenson, 47, a Protestant father of three, who works for a local taxi company in the Northern Irish town of Lisburn.

Stevenson showed Reuters a text message which had been circulating among the Protestant community.

To all Ulster men and women. Two of our British soldiers were slaughtered and 4 others critically wounded by republican filth last night. This txt signals that the war has begun. We must be ready to fight once again. Send to all loyalists. Let the battle begin, it said.

Sinn Fein President Gerry Adams, for years the face of republican opposition to British rule in Northern Ireland, called for calm.

There cannot be on the one hand any succor for those who carried out this action but neither can there be any sort of a security response from the British, he added.

Troops patrolled Northern Ireland's streets during decades of sectarian violence but stood down in 2007, leaving security in the hands of the police.

Putting them back on patrol would be divisive and antagonize Sinn Fein, handing the Real IRA, which is thought to number about 100 people, a propaganda coup.

A maximum of 5,000 military personnel are now stationed in Northern Ireland.

We will continue to live in Northern Ireland as part of the community as we have done since 2007 and as we do in Great Britain, Brigadier George Norton, Northern Ireland garrison commander, told reporters.

We will not be deterred from our primary role of preparing and training for operations overseas, he added.

The soldiers were the first troops to be killed in the British-ruled province since 1997.

They were named as Cengiz Azimkar, a 21-year-old from north London, and Mark Quinsey, who was 23 and from the central English city of Birmingham.

(Additional reporting by Carmel Crimmins)

(Writing by Keith Weir and Jonathan Saul; Editing by Mark Trevelyan)

Afghanistan