Image copyright AFP

When Mikhail Gorbachev resigned almost exactly 25 years ago - bringing the USSR to a sudden end - he had been left little choice by the leaders of Russia, Ukraine and Belarus. The three men had signed a treaty 17 days earlier dissolving the Soviet Union - a momentous decision which appears to have been taken with very little planning.

By December 1991, the Berlin Wall and Eastern European communism were long gone. But the Soviet Union still existed, ruled by the Communist Party with Mikhail Gorbachev at its head. He had been weakened by a hardline coup in August 1991, but his biggest problem, as the year drew to a close, were the independence movements in a number of Soviet republics.

The USSR could survive without the Baltic republics - Estonia, Latvia and Lithuania - but not without Ukraine or Russia.

The newly elected president of Ukraine, Leonid Kravchuk, was looking for a way to break free from Moscow, and the president of Russia, Boris Yeltsin, was eager to wrest more power from Gorbachev. So when they agreed to meet on 8 December, with their Byelorussian counterpart, Stanislav Shushkevich, it could have been predicted that nothing good for Gorbachev would come of it.

Image copyright Alamy

And yet, it seems there had been no agreement in advance to deal the USSR a fatal blow.

Shushkevich insists that the agenda of the meeting was to discuss the oil and gas supply from Russia to Belarus over the winter.

According to a popular myth, we drafted our agreement while drunk - this is completely wrong! Stanislav Shushkevich, Former leader of Byelorussia

"Our economy was in crisis, we could not pay for the supplies, and had no-one to lend us the money - so we wanted to ask Russia to help us out, so that we don't freeze that winter. That was the aim of our meeting," he says. "We invited Ukraine also, because we wanted to be transparent and didn't want to do deals with Moscow behind Ukraine's back."

Annoyingly, our telephone conversation is constantly interrupted. Shushkevich explains that even now, a quarter of a century later, the topic of the dissolution of the USSR is still banned in Belarus. The interruptions on the phone line, he says, are the work of Belarusian secret services.

But Leonid Kravchuk has a completely different memory of the meeting.

"When Shushkevich talks about oil and gas - I have no idea what he is on about!" says the former Ukrainian leader.

"I hadn't been told anything about oil and gas. I thought I was going there to discuss the future of the USSR. The country was being torn apart by contradictions, its people exhausted by crises, conflicts, wars and queues. We gathered in Byelorussia to discuss where the country was heading, and perhaps to sign a petition, or a declaration, in order to draw attention to the crisis we were in."

Image copyright AFP Image caption The year had begun with calls for Gorbachev to resign after a bloody crackdown in Lithuania

But whatever the pre-arranged agenda all three leaders - the Russian president Boris Yeltsin included - knew that calling a meeting without informing Gorbachev first was risky.

"Of course the Soviet KGB could arrest us, on orders from Gorbachev - because the Soviet KGB was obviously under Gorbachev's command, not Yeltsin's," says Shushkevich.

The most we would allow ourselves was a drop of brandy every time we adopted a new article Stanislav Shushkevich, Former leader of Byelorussia

"But the head of our local Byelorussian secret service, Eduard Shirkovsky, kept in touch with Yeltsin's secret services. For about a fortnight before the meeting, he had assured me daily that there was no danger of our arrest.

"Interestingly, later, when Shirkovsky retired and went to live in Russia, he said exactly the opposite. He expressed regret that he hadn't arrested us back in 1991! So you can see how difficult it was to tell what was going on."

At the end of 1991, however, these regional leaders saw Mikhail Gorbachev as largely irrelevant.

"Sure, he was still a figurehead, but he had no power!" says Kravchuk.

"After the coup against him in August 1991, he had lost power. He did come back afterwards, but he had no real power any more. We saw that the power was devolving to the leaders of the republics. Although Gorbachev had wanted to re-organise the country into a new kind of union, he could not really do it."

So, on 7 December 1991, the Russian leader Boris Yeltsin, Ukrainian leader Leonid Kravchuk and Byelorussian leader Stanislav Shushkevich headed for a country estate, reserved for top-level Communist officials, in Belavezha, near the Polish border.

Image copyright Alamy Image caption Belovezhskaya Pushcha, where the treaty was signed

"This was a very luxurious residence, set up to receive the top Soviet officials," says Shushkevich.

"As was usual for such meetings, a steam bath visit was scheduled. Normally, after the steam bath, there would be plenty of alcohol on offer - but on this occasion, instead of alcohol, we had a massage. The meeting was organised in the best Soviet traditions, with plenty of food, plenty of drink, plenty of facilities to relax, and an opportunity to go hunting."

The next day, on 8 December, at 09:00 the leaders, with their prime ministers and various officials in tow, gathered for the negotiations - still apparently unclear what they were about to discuss.

The first suggestion came from a Russian adviser, Gennadi Burbulis - and it could not have been more radical.

Find out more

Image copyright AFP Image caption Kravchuk and Shushkevich (seated left), with Yeltsin (right)

Listen to Dina Newman's report on the signing of the treaty dissolving the USSR for Witness, on the BBC World Service

Explore other Witness episodes on the collapse of Soviet power

"I will remember this sentence to the end of my life," says Shushkevich.

"It is the opening statement of our agreement, the only one which was adopted without any arguments. 'The USSR, as a geopolitical reality, and as a subject of international law - has ceased to exist.' And I was the first to say that I would sign up for this."

The agreement would render the Soviet president Mikhail Gorbachev irrelevant, while giving more power in Moscow to Russia's president Boris Yeltsin.

But putting an end to the centuries-old Russian empire and its successor, the USSR, was a big step. Years later, many wondered whether the three politicians were entirely sober when taking this momentous decision?

"According to a popular myth, we drafted our agreement while drunk," says Shushkevich. "This is completely wrong! Of course, it was a typical Soviet arrangement, and alcohol was freely available everywhere in the residence - but no-one touched it. The most we would allow ourselves was a drop of brandy every time we adopted a new article."

In the next few hours, 14 articles in all were adopted. By about 15:00, the document confirming the dissolution of the USSR was ready. The next step was to inform the world, and the Byelorussian leader drew the short straw.

Image copyright AP Image caption A deer in the Belovezhskaya Pushcha national park

"Yeltsin and Kravchuk said to me jokingly: 'We have voted to nominate you to inform Gorbachev.' And then I said: 'Kravchuk and myself nominate you, Mr Yeltsin, to call your good friend, the US president George Bush.'

It was a difficult conversation... Gorbachev was angry Leonid Kravchuk, Former Ukrainian leader

"I dialled Gorbachev's office in Moscow - but they wouldn't put me straight through, they kept passing me from pillar to post, and I had to explain who I was over and over again. Meanwhile, Yeltsin, seeing that I was on the phone to Moscow, dialled President Bush. [Andrei] Kozyrev, the [Russian] minister of foreign affairs, was on the other line, translating Bush's comments."

The Ukrainian leader Leonid Kravchuk was listening in.

"As far as I remember, Bush asked two questions. Will the successor state take on all the obligations of the USSR? And second, what will happen to the Soviet nuclear weapons?" says Kravchuk.

"We couldn't comment on the nuclear weapons, since we hadn't discussed that question yet. But with regards to the obligations, Yeltsin said, 'Yes, we will take them on.'"

By that time, the Byelorussian leader, Shushkevich, had finally got through to Gorbachev, and again, the Ukrainian leader was listening in.

"It was a difficult conversation," says Kravchuk. "Gorbachev was angry with Shushkevich, saying, 'What have you done? You have turned the whole world upside down! Everyone is alarmed!' But Shushkevich stayed calm."

To this day, the affable Byelorussian leader is clearly proud of the way he handled that crucial conversation with Moscow.

"I explained to Gorbachev the kind of document we were about to sign. He responded, rather patronisingly, 'And what about the the international community? Have you thought of their reaction?' And I answered, 'Actually, Boris Yeltsin is talking to President Bush right now - and Bush doesn't seem to mind! In fact, he is in favour!'"

Image copyright AFP Image caption Shushkevich and Kravchuk, later in December 1991

During the next hour, the three leaders signed their historic document at a press conference called for the purpose. After the conference, it was time to go home - and that's when Stanislav Shushkevich got cold feet.

"As I was heading back home, I was listening to the radio in the car, to find out what was going on in the world. The first thing I noticed, the names Yeltsin and Kravchuk came up a lot - but when they came to my name, they couldn't pronounce it properly. 'Chuchkevich, Sheshkevich, Sharkevich,' and anything in between.

"And whatever frequency I tuned into I heard, over and over again, Kravchuk, Yeltsin, and sh… vich… ch… vich… and other variations on my name. And that's when I realised, we were big news. Until then, I had been so busy, I hadn't had time to think.

"But at that moment, I got scared. I thought: 'Eighty-two per cent of our regional parliament are Communists. If they don't ratify this agreement - I will have made a mistake, and this will be the end of my political career!'"

But all three regional parliaments ratified the agreement, and other Soviet republics joined in over the next couple of weeks. On 25 December, President Gorbachev resigned, and the USSR was no more.

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