|According to media sources, NATO planes bombed Gaddafi's compound for the second time on Tuesday [EPA]
NATO's secretary-general has said he will use a two-day meeting of NATO alliance defence ministers to push for broader participation in Libya by other members of the organisation.
Anders Fogh Rasmussen asked for more countries from the 28-nation alliance to share the costs and risks involved in the campaign at a meeting at NATO's Brussels headquarters on Wednesday.
"Obviously some of those allies and partners carrying the heavy burden start to ask whether it would be possible to broaden the participation a bit," he said earlier this week.
"That is also the essence of our alliance: that allies that actually have the necessary assets at their disposal, also contribute those assets, based on the principle of solidarity."
NATO is not publicly releasing figures on how many nations are involved in the strikes on Libya, but it is thought to be about 17.
One of the alliance's most powerful members, Germany, is refusing to take part in the mission and that looked unlikely to change on Wednesday.
"We will not change our position concerning the military action. We will not participate,'' Christian Schmidt, Germany's secretary of state, said.
Sweden's government announced on Wednesday that it reached a deal with opposition parties to extend the mission of Swedish jets taking part in Libya reconnaissance missions by three months when it expires on June 22.
Under the plan, five of the eight Swedish jets currently taking part in the operation will continue to carry out reconnaissance missions over Libya.
Meanwhile, Spain has officially recognised Libya's rebel National Transitional Council as the country's legitimate representative, Trinidad Jimenez, the Spanish foreign minister said during a visit to rebel-held eastern Libyan city of Benghazi.
"I'm here today to confirm that the National Transitional Council is the only legitimate representative of the Libyan people," Jimenez told reporters on Wednesday.
Liam Fox, the UK defence secretary, said he wanted to see "increased urgency in some quarters" for the Libya campaign.
"The United Kingdom has been very forward-leading, very clear that we want to see the Libyan people safe from the excesses of the Gaddafi regime," he said.
"We will want to push that point today."
NATO jets continued to pound the Libyan capital, Tripoli, in daylight raids on Wednesday, in what appears to have become an escalating mission to oust Muammar Gaddafi, the Libyan leader.
British and French attack helicopters struck for the first time inside Libya over the weekend, significantly ramping up NATO's operations.
Ten explosions shook Tripoli on Wednesday, a day after the alliance's most intense wave of air raids of the two-month campaign.
Wing Commander Mike Bracken at NATO's Libya operations headquarters in Naples, Italy, told the Associated Press news agency that there had been "increased tempo over recent days over Tripoli" but he stressed that "Gaddafi as an individual has not been a target and won't be a target".
An alliance official said that striking at Libyan military and intelligence command and control centre such as those attacked in Tripoli had "a direct correlation" with protecting civilians because it meant Gaddafi's forces could no longer receive orders from commanders.
He spoke on condition of anonymity because he was not authorised to speak publicly about the mission.
Meanwhile, a defiant Gaddafi vowed on Tuesday to fight to the death.
"We will not surrender: we only have one choice - to the end! Death, victory, it does not matter, we are not surrendering!'' Gaddafi said on state television.
Last week, NATO extended its mission, named Unified Protector, for a further three months.