London : US and Britain have promised no "let-up" in an international military campaign aimed at pressuring Muammar Gaddafi, the Libyan leader, to step down.
Speaking at a joint press conference in London on Wednesday, Barack Obama, the US president, and David Cameron, the British prime minister, reiterated calls for Gaddafi to go.
"I believe that we have built enough momentum that as long as we sustain the course we're on, he will step down," Obama said.
"Ultimately this is going to be a slow, steady process in which we're able to wear down the regime forces."
Libya has been wracked with conflict for months as Gaddafi seeks to crush an uprising against his 41-year rule.
European and US forces mounted air raids on Libya on March 19 after the UN Security Council authorised "all necessary measures" to protect civilians from Gaddafi's forces.
The US president, in the UK as part of a six-day European tour, ruled out a deadline for ending the US role in Libya, saying the mission would end in a timely fashion.
Cameron backed Obama, saying: "I absolutely agree that given the progress that has been made over the last several weeks that Gaddafi and his regime need to understand that there will not be a let-up in the pressure that we are applying."
He said he believed Gaddafi was "ultimately going to step down".
Their comments come amid complaints among some NATO countries about the reduced US role in the Libya operation since NATO took over command.
Legislators in Britain and France have complained that their nations are shouldering an unfair burden in the Libya campaign, particularly at a time when budget cuts have hit defence spending.
But earlier in the day, William Hague, the UK foreign secretary, dismissed suggestions that Britain was among the countries upset about the US contribution to the mission.
Speaking to the BBC, he said he had "no criticism" of his American allies.
