David Miliband flew to Ukraine today to deliver the most passionate and precise speech by a member of the British Government on the crisis in Georgia, with strong warnings to Russia and warm encouragement for the two smaller former Soviet countries.

That does not mean that the Foreign Secretary went as far in encouraging Ukraine – or Georgia – as he might have done. He was vague on whether Britain will back a formal offer of a plan for membership of Nato in December, which suggests that the Government has not entirely shed its unfortunate tactical ambiguity of earlier this year.

There was a strong element of what Miliband does best: preaching democracy to new democracies – which are more than converted to the principle – while asking for little in return for his praise that would be awkward for them to give.

All the same, this was a powerful speech that needed to be delivered. In a blunt lecture to Russia, he said that it offers no rival ideology to liberal democracy other than force, and that obsessive delusion about the return of its past empire could shut it out from the modern world for decades.

“I have come with one reason above all others,” Miliband said. “In the midst of the Georgia crisis, I want to reaffirm the commitment of the United Kingdom to support the democratic choices of the Ukrainian people.”

He added, in language significantly toughened (according to aides) in the 24 hours since Russia recognised the breakaway Georgian provinces of South Ossetia and Abkhazia: “The Russian President [Medvedev] says he is not afraid of a new Cold War. We don’t want one. He has a big responsibility not to start one.”

The Ukrainian trip, which he conceived a week ago on his dash to Tbilisi, is an astute choice. The country threatens to be a vacuum: a fragile democracy, with a Government torn by the rival halves of the country – the west seeing itself as part of Europe, the east as part of Russia.

Moscow broods over it all with an historical possessiveness, outraged that Ukraine, like Georgia, dreams of joining the EU and Nato. Volodymyr Ohryzko, the Ukrainian Foreign Minister, today rejected the threat that Ukraine “might end up in Georgia’s situation”, but British officials acknowledged reports that Russia had been handing out passports in Crimea, the Ukrainian region with strong pro-Russian feelings.

Miliband added: “One country plunged into crisis is quite enough.” Advocating hardheaded engagement with Russia, he warned it that the West should “raise the costs to Russia of disregarding its responsibilities”.

He challenged Vladimir Putin’s frequent assertion that Russia has not been rewarded for its concessions to the West, arguing that “we have offered Russia extensive cooperation with the EU and Nato, membership of the Council of Europe and the G8”, as well as summits and meetings.

Miliband gave a brisk rebuttal of Russia’s equation of South Ossetia and Abkhazia with Kosovo, noting that they had not suffered the “ethnic cleansing” that Serbia had inflicted on that province. He pointed to the slump in the Russian stock market and cautioned about the threat to prosperity from “short-term military gains”.

His youthfulness (and he has a new haircut, cutting off the one white tuft at the front, making him look even younger) was no bad thing in the context, as he warned Russia that it would lose its place in a modern future. But the core of the speech was always going to be his response to Ukraine’s hope of joining the EU and Nato. More on the first than the second, it turned out. “It is clear to me, standing here today, that this is a European country,” he said, adding that “once it fulfils the criteria, it should be accepted as a full member, and we should help you get there”.

On Nato, he cited the alliance’s promise at its summit in April of eventual membership for Ukraine and Georgia. But while voicing support, he did not say that Britain would lobby for giving the countries a membership action plan – the start of the process – when Nato foreign ministers meet in December. This echoes Gordon Brown’s unattractive evasions at the April summit when he allowed tactical silence to become a policy.

You can’t accuse Miliband of invisibility. Democracy is the subject on which he is most fluent, and this trip demanded of him the skill that he has not often shown – flying home brandishing a deal extracted from the other side. This speech was far better than previous ones in the precision of its warnings to Russia and promises to Ukraine: the right words, in the right place, at indisputably the right time.

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