Tough Love in Tripoli

Jack Straw stood in the middle of the Foreign Office's opulent Locarno Room yesterday to proclaim the success of the government's policy of engagement with "rogue states".

Alongside the foreign secretary was his Libyan counterpart, Abdul Rahman Mohammed Shalgam, the two men having emerged from the highest-level meeting between Libya and Britain for more than two decades.

In contrast with the US, which lists Libya as a "state of concern" alongside Iran and Syria, British policy since Labour came to power in 1997 has been to enter into dialogue with these countries, to seek "constructive engagement", or "critical engagement", as it is sometimes called.

As a policy, it seems like a success. Libya has promised voluntarily to dismantle its weapons of mass destruction. The Syrian president, Bashar al-Assad, regarded as a pariah by Washington, made a visit to the UK and met Tony Blair in Downing Street. In the autumn, Mr Straw led a European mission to Iran that, at least temporarily, resolved a crisis over Iran's alleged nuclear weapons programme.

Constructive engagement was initiated in 1997 by the then-foreign secretary, Robin Cook. It has been actively pursued by his successor, Mr Straw, and the policy of negotiation contrasts favourably with Washington's resolution of awkward international issues through wars in Afghanistan and Iraq.

The response of the US administration to Britain's approach has been mixed. At times, the US state department has been supportive and engaged. Mr Straw phoned the US secretary of state, Colin Powell, just before he met Iranian leaders in Tehran last autumn and again immediately afterwards.

If Libya, Syria and Iran fall into line, the US administration could claim these as successes in its "war on terror". George Bush could say that they are only decided to fall into line because they had seen what happened in Afghanistan and Iraq.

But there are others in the US administration who remain sceptical about Libya, Syria and Iran.

Libya is the likeliest of the three to end happily because its leader, Muammar Gadafy, appears to want to end his country's alienation from the west and embrace the economic benefits that would accrue from a normalisation of relations.

But questions are being raised about just how extensive and advanced the country's
WMD programmes really are. Has Libya chosen to exaggerate the extent of its weapons programme? And does it suit Britain and the US to go along with this?

The Libyan foreign minister undercut the Foreign Office by playing this down yesterday. He said that Libya had scientists with nuclear know-how and the material they needed, but that did not mean they intended to make a bomb. Just because you have water, flour and fire does not mean you intend to make bread, he said.

He took some of the shine off the British triumph by saying that while there had been secret talks with the British, Libya was engaged also engaged with Washington and had been speaking to US officials privately since 1992.

There is also widespread scepticism about Mr Assad, especially as to whether he has sufficient power within Syria to make the changes necessary to satisfy the west. Demands include the withdrawal of Syrian forces from the Lebanon, an end to support for Hizbollah and groups fighting against Israel, and the abandonment of its alleged chemical and biological weapons programmes.

But Iran remains the biggest problem. Even at the Foreign Office there are those who remain wary, unconvinced that the country has truly abandoned its ambition to build a nuclear bomb.

Britain has invested a lot of time in Iran. Mr Straw has made half-a-dozen visits, making it the most frequented country by the foreign secretary apart from the US - where he travels to visit both the US government and the UN - and Belgium - where he attends regular EU meetings. Even Prince Charles was in Iran earlier this week, albeit for what British officials insisted was a humanitarian, non-political visit to the survivors of December's earthquake in Bam.

It could all still go wrong, and there is a good chance that it will. But the Foreign Office cannot be faulted for at least opting for diplomacy rather than confrontation.

Ewen MacAskill is the Guardian's diplomatic editor