Defence Secretary Des Browne has denied claims that commanders of British troops in Afghanistan have asked for extra fighting forces or air support.
British troops are fighting Taleban insurgents in Helmand
He told the BBC there was a request for more engineers but rejected reports an extra 1,000 troops were being deployed.
Two UK soldiers killed on Saturday have been named as Cpl Peter Thorpe and L/Cpl Jabron Hashmi, a Muslim.
The deaths of the 3rd Para Battlegroup men means five British troops have been killed in Helmand in three weeks.
The two men were killed in clashes with Taleban militants.
The family of Lance Corporal Jabron Hashmi, 24, who was the first British Muslim soldier to die in the 'war on terror', said he had hoped to help foster greater understanding in the Army.
"Jabron wanted to join the British Army as a young boy growing up in Pakistan.
"He felt privileged to represent the Army as a Muslim British Pakistani who wanted to use his background and position to contribute at a time where there exists a lack of understanding of cultures, ideologies and religious identities," they said.
L/Cpl Hashmi's brother, who did not want to be named, described the family's mood.
"Obviously a tragic loss, a sense of devastation, in particular my mother. But at the same time a sense of pride in terms of what Jabron was committed to doing."
Cpl Thorpe's family were too distressed to issue a statement, but his commanding officer called him: "An outstanding man, highly motivated, talented and tremendously popular".
US-led coalition forces said 20 militants were killed in clashes in Helmand on Sunday.
And Defence Secretary Des Browne told BBC's Newsnight there had been "significant progress" in tackling the opposition.
He added: "We have had a conspicuous degree of success against them, I have to say, with the potent force that we have deployed into Helmand province because we always anticipated that there would be a degree of resistance."
Earlier, in his Commons statement, Mr Watson denied claims from Opposition politicians that Britain's role had become confused.
L/Cpl Jabron Hashmi and Cpl Peter Thorpe died in a grenade attack
He said: "Despite press reports today, commanders have not asked for extra infantry or air cover.
"The latest requests to the chiefs of staff included requests for enablers and engineering equipment."
Earlier, Brigadier Ed Butler, who is in overall command of the UK troops in the country, had told the BBC that he had asked for extra resources.
"I've put in requests which are being considered back in London as we speak to take account for the change in circumstances," he said.
The Guardian reported that hundreds of extra combat troops would be deployed to southern Afghanistan because of the "unexpected strength" of Taleban fighters.
It said the plans had been drawn up by the MoD as part of a review of tactics by British and Nato commanders.
Mr Watson said the level of forces in the country was constantly being discussed with Nato, but said he could not give details of those discussions.
The government's decision to answer a Commons question came after the Conservatives called for a statement.
Shadow defence secretary Dr Liam Fox said ministers needed to be frank with the public on the risks faced by British troops in Afghanistan, and the nature of their mission there.
"The government has certainly given the impression to both Parliament and the public that this mission is less complex and dangerous than I believe it to be," he said.
Former Defence Secretary John Reid had announced that as many as 5,700 British forces might be in Afghanistan at the peak of the deployment.
Mr Watson reiterated that these servicemen and women would be both combat forces and engineers involved in rebuilding projects.
MoD officials say engineers are already starting to go home after completing their tasks as combat forces continue to arrive, and so the 5,700 will probably not be reached.
The UK troops in Afghanistan are part of a three-year Nato task force charged with helping the Afghan government to stamp its authority on the region.