Nato steps up strikes on Tripoli in bid to break Gaddafi's resistance

Nato was showing signs of escalating its attack on the Libyan regime yesterday after its heaviest bombing yet of Tripoli and reports that France and Britain are to deploy helicopter gunships against pro-Gaddafi forces in a bid to break the stalemate.

Huge plumes of black smoke rose over the Libyan capital early yesterday after allied aircraft struck at least 15 targets in central Tripoli in an intense 30-minute period of bombing directed at the area of Colonel Gaddafi's Bab-al-Azizia compound.

The assault, which started at around 1am, came only hours after America's top Middle East official, Jeffrey Feltman, visited opposition leaders in the western rebel capital of Benghazi and the French Defence Minister disclosed plans to use attack helicopters as soon as possible. The minister, Gérard Longuet, said France and the UK would be bringing in the low-flying helicopters, which have a high capacity to attack mobile military targets but are also more vulnerable to retaliatory fire from the ground.

Nick Harvey, Britain's Armed Forces minister, confirmed in Parliament yesterday that the Government was considering using helicopters to boost Nato's operations as part of a "tactical shift", but said no firm decision had yet been made.

Yesterday's developments appear to mark a new determination on Nato's part to break the military stalemate which has left rebels in control of eastern Libya but the regime still in control of much of the west of the country, including Tripoli itself.

Moussa Ibrahim, spokesman for the regime, said overnight air strikes had hit a compound used by the Popular Guard, an auxiliary armed force. He said that commanders had cleared most of the compound because of fears that it would be hit and that casualties – which he put at three dead and 150 wounded – were civilians living near by.

As jets flew unusually low over Tripoli during the night, there were audible bursts of anti-aircraft fire. People could be heard screaming outside a hotel where journalists were staying. Pro-Gaddafi loyalists fired guns, shouting their support for the Libyan leader.

Mr Longuet had earlier said that attack helicopters would be deployed to target Libyan tankers and ammunition trucks in urban areas, with the aim of causing fewer civilian casualties than if high-flying bomber jets were used. The fear of causing civilian casualties has inhibited Nato from launching attacks on Gaddafi forces in crowded urban areas.

The French Defence Minister said that his country would largely be using Gazelle helicopters, which have been in service for around four decades. But it would also be open to France to deploy the more up-to-date Tiger attack helicopters. Britain has at its disposal American-made Apache helicopters, versions of which have been used by US forces in Iraq and Afghanistan.

Meanwhile the US State Department lost no time in calling the visit by Jeffrey Feltman, Assistant Secretary of State for Near Eastern Affairs, "another signal of the US support" for the rebels' National Transitional Council, which it called "a legitimate and credible interlocutor for the Libyan people".

Mr Feltman said that he had delivered an invitation on President Barack Obama's behalf to the rebels to establish a representative office in Washington – a move he called "an important milestone in our relationship with the National Transitional Council".