The head of the armed forces has said UK operations can continue in Libya as long as necessary - after concerns were raised by the head of the Royal Navy.
General Sir David Richards told the BBC: "We can sustain this operation as long as we choose to".
Nato took over the Libyan mission on 31 March, initially for 90 days but that has been extended by a further 90 days.
Navy chief Admiral Sir Mark Stanhope said on Monday priorities must change if the mission exceeds six months.
The Nato mission - enforcing a no-fly zone over Libya to protect civilians using "all necessary measures" short of a ground invasion - was prompted by Libyan leader Col Muammar Gaddafi's violent response to an uprising against his 41-year rule.
It was mandated by the United Nations, and led by France, Britain and the US until 31 March, when Nato took over.
Having initially been given 90 days - which would have run out on 27 June - the mission has now been extended for a further 90 days.
World leaders including UK Prime Minister David Cameron have said Colonel Gaddafi must go but despite months of air strikes on military targets, the Libyan leader remains in control of the capital Tripoli and much of the west of the country.
As the UN resolution specifically ruled out ground troops, concerns have been raised the action could lead to stalemate.
General Richards told the BBC: "We can sustain this operation as long as we can."
He said Adm Stanhope's comments had been "misconstrued" adding: "We can sustain this operation as long as we choose to. I'm absolutely clear on that."
On Monday Adm Stanhope, told a media briefing: "How long can we go on as we are in Libya?"
"Certainly in terms of Nato's current time limit that has been extended to 90 days, we are comfortable with that. Beyond that, we might have to request the government to make some challenging decisions about priorities."
He continued: "If we do it longer than six months we will have to reprioritise forces. That is being addressed now.
"It could be from around home waters. I will not prejudge what that decision will be."
He did not say what might have to be reprioritised and insisted he was not calling for a re-examination of the decision to cut the Ark Royal and its fleet of Harriers.
Critics of the Strategic Defence and Security Review (SDSR) have suggested the Libya mission illustrated the importance to the Navy of an airport carrier.
Adm Stanhope admitted Harrier jets could have been deployed in 20 minutes rather than the 90 minutes taken to send Tornado and Typhoon aircraft from the Gioia del Colle air base in Italy.
But he conceded they would not have been able to use Brimstone missiles carried by the Typhoons and Tornados.
Last week Defence Secretary Liam Fox denied the Libya mission had a six-month deadline.
Responding to Adm Stanhope's comments Dr Fox said the Libya operation showed the UK was still "a leading military power with the fourth largest defence budget in the world" and said the spending review would not be reopened.
"We continue to have the resources necessary to carry out the operations we are undertaking and have spare capacity with the Royal Navy Cougar Taskforce which is currently on exercise in the Gulf."
Shadow defence secretary Jim Murphy said Adm Stanhope's comments were "incredible".
"The country will be dismayed to hear that the operation in Libya could have been conducted more cheaply and more effectively had the government taken a different approach," Mr Murphy said.
"It is vital that ministers tell us now how they intend to equip the mission in Libya should it go beyond the six-month mark."
On Sunday RAF Tornados and Typhoons conducted strikes against two ammunition depots, destroying nine underground storage bunkers, the Ministry of Defence said.
A spokesman said British Army Apache attack helicopters were also asked to intercept two high-speed inflatable boats detected approaching Misrata - amid concerns they were being used by Gaddafi forces to attack the harbour.