British defence chiefs are applying pressure on other Nato countries to intensify the bombing campaign against Muammar Gaddafi's regime amid deepening concerns that military action will end in stalemate.
Nearly two months since the start of air strikes against Libya, Nato chiefs fear divisions within the alliance, and at the UN, will lead to fewer air strikes just at a time when, they claim, the regime is starting to feel the pinch and even its core support showing signs of cracking.
They want Nato to expand its targets, as the UK and a number of smaller Nato nations already have done, to include more static targets such as command and control centres and not only those posing a direct and clear threat to Libyan civilians, such as tanks and artillery.
Well-placed British government officials made this plain on Sunday as General Sir David Richards, chief of the defence staff, said that he wanted the rules of engagement changed so that attacks can be launched against the infrastructure propping up Gaddafi's regime.
"The vice is closing on Gaddafi, but we need to increase the pressure further through more intense military action," Richards told the Sunday Telegraph.
"We now have to tighten the vice to demonstrate to Gaddafi that the game is up and he must go," he added. "We need to do more.
"If we do not up the ante now there is a risk that the conflict could result in Gaddafi clinging to power."
Richards added: "At present Nato is not attacking infrastructure targets in Libya. But if we want to increase the pressure on Gaddafi's regime then we need to give serious consideration to increasing the range of targets we can hit."
Though he said that Nato forces were not targeting Gaddafi directly, the Libyan leader could become a legitimate target if he was discovered directing attacks against Libyan civilians.
The UN security council resolution allowed Nato to use "all necessary means" to protect civilians.
"We are not targeting Gaddafi directly, but if it happened that he was in a command and control centre that was hit by Nato and he was killed, then that is within the rules," Richards said.
Taking a much tougher line than earlier in the conflict when he made clear Gaddafi was not a target – and was sharply criticised by Downing Street for his pains – Richards now says that Gaddafi cannot be allowed to remain in power.
"If Nato withdraws its forces with Gaddafi still in power, then there is a significant risk that he will launch fresh attacks against the rebels," he said.
Significantly, Richards added: "The prime minister and I are on the same page. We are in total agreement that the only solution to this conflict is for Gaddafi to go."
Liam Fox, the defence secretary, admitted on Sunday that a number of Nato countries were "less happy" with Britain's decision to extend the number of targets, to include command and control centres and what he called "intelligence networks". Speaking on BBC1's Politics Show, he said: "Not all Nato countries take the same view."
Fox added that if Gaddafi regime commanders chose to be in a command and control centre it was "a risk they take".
Concern among senior defence officials is likely to be increased further as Baroness Amos, former Labour cabinet minister and now top UN official for humanitarian relief, responded to Richards's comments by calling for a temporary halt to hostilities.
She called for a political solution as soon as possible, adding that "any upscaling of the fighting will have a significant impact on the people".
Adrian Mitchell, the international development secretary, said it was not the coalition engaged in air strikes, but Gaddafi"s forces, who were preventing medical supplies and food from being distributed. The military campaign was not about "targeting individuals", he said.
