"There were no objections, and no other serious candidates," one Nato diplomat said, as the big countries made clear their support for Mr Robertson, whose surprise nomination was announced by Tony Blair on Friday. The alliance is expected to move quickly to rubber stamp the appointment, perhaps as early as today.
However, all 19 member states have to agree, and yesterday three delegations did not yet have permission from national capitals to approve Mr Robertson at a formal session of the alliance's decision making body, the North Atlantic Council.
Nato is anxious that there should be no vacuum over the summer, although the outgoing secretary-general, Javier Solana, who led the alliance into war against Serbia, does not intend to quit until the end of September.
With the support of the United States, Britain, France, Germany and Italy, the British secretary of state is virtually certain of the post, which would make him the third British secretary-general. Lord Ismay, a member of Churchill's wartime cabinet, was the founding secretary-general and Lord Carrington served from 1984-88.
Mr Robertson's move will necessitate a cabinet reshuffle in Britain, with John Reid, the Secretary of State for Scotland and a former armed forces minister, expected to fill Mr Robertson's job, and Brian Wilson likely to take the Scottish portfolio.
Washington played a decisive role in Mr Robertson's nomination by making it clear to Mr Blair that a British candidate of sufficient stature would win the post. The expectation that Rudolf Scharping, the German Defence Minister, would take up the post was dashed when he said he wished to stay in the German government. Having missed out on other prizes in the international and European jobs carve-up, the United Kingdom was in line for a top position.
Mr Robertson is well placed to deal with the tensions between Europe and the US which afflict Nato policy. One US source said: "He has been very effective in Nato ministerial meetings and at the Nato summit in Washington. He can work with the French as was shown at St Malo [where last year's Anglo-French defence initiative was agreed]. He has a high profile in Washington among Nato-watchers." The US believes Mr Robertson can see through initiatives to modernise Europe's armed forces.
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