Lord Ashdown of Norton-sub-Hamdon is to be the new United Nations “super-envoy” in Afghanistan, charged with overhauling the reconstruction of the country at a time of low morale and increasing attacks by the Taleban.

UN sources in New York confirmed the appointment yesterday evening, although an official announcement was delayed as Lord Ashdown bargained for more power.

He is expected to be charged with coordinating the Western reconstruction and aid effort, pulling together international agencies, foreign donors, the Afghan Government and Nato military forces.

The task is unlikely to be easy, as much of the effort is duplicated, ineffective and short-term, while ordinary Afghans are increasingly angry that they are seeing so little of the billions of pounds that have been donated to the country.

Western diplomats, as well as Afghans disillusioned with President Karzai, will be hoping that Lord Ashdown can repeat his success as the UN High Representative in Bosnia between 2002 and 2006. But he will have less power in Kabul, and the problems he faces at a crucial point in the six-year Western engagement in Afghanistan could make him yearn for his time in Sarajevo. The former Royal Marine commando, 66, had appeared to rule himself out of the Kabul job last year, when he was very critical of the international community’s handling of the postTaleban period and predicted defeat for the West.

“We are losing in Afghanistan and I do not think anyone has thought through the consequences,” he said in June after the publication of his book, Swords and Ploughshares. “This could be far worse than Iraq. If Afghanistan goes down, it will be impossible to hold Pakistan and the consequences of that are horrific . . . It is also a catastrophe in the making for Nato.”

Lord Ashdown, who served in Kenya, Kuwait, Borneo and Northern Ireland, has set out his conviction that an invading force has to establish authority over its captured territory in the “golden hour” immediately after intervention. In Afghanistan’s case the US-led forces overthrew the Taleban in 2001, but failed to seize control of the country and allowed the militants to regroup, rearm and counter-attack. The former Liberal Democrat leader believes that establishing security and rebuilding the economy is a greater priority than democracy. In Afghanistan, reconstruction has progressed slowly, security has deteriorated and corruption is rampant. Early polls were held but the Government is weak and many former warlords have returned to power.

In his book, Lord Ashdown makes the point that there are 72 different caveats among the 32 nations contributing to the Nato force, with countries such as Germany avoiding combat. He also criticised the aid effort. According to his book there were 24 aid organisations providing help after 2001 but they failed to coordinate their efforts for five years, leading to duplication and inefficiency.

Afghanistan fails to meet any of Lord Ashdown’s criteria for successful intervention, but he may be the only person with the experience needed to salvage the mission. Expectations are high that a dynamic new “super-envoy” will sort out the muddle and drift in Kabul and reverse the deterioration suffered in the past three years.

One Afghan businessman said: “He is the last chance to save Afghanistan. I pray that it is him who will run our country, and not our useless President, who has so far managed to squander the best opportunity Afghanistan has had in 250 years.”

Lord Ashdown is likely to face some serious Afghan opposition as well. Former Northern Alliance warlords will dislike having a powerful new civilian in Kabul and will fear war crimes proceedings against them.

He will arrive to find much good-will. The US, which has by far the most important role in Kabul, has backed Lord Ashdown’s candidacy with enthusiasm, and the sense that a co-ordinator is urgently needed has been growing for months. While deciding whether to take the job Lord Ashdown met President Karzai in Kuwait and the two reportedly got on well. Their relationship will be critical but it is unlikely to be smooth all the time. The expulsion of an EU and a UN diplomat from Afghanistan last month after they were accused of talking to the Taleban was seen in part as a warning shot to Lord Ashdown.

Dealing with US generals could prove just as tricky. There has been friction between the UN and the US over civilian casualties and longstanding distrust between aid workers and the military who blame each other for the failure to secure the south.

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