In December 1999, when Russian President Boris Yeltsin was weak and his power was leaching away, an ambitious neighbor, President Alexander Lukashenko of Belarus, agreed to unify his country with Russia.

Yeltsin would step down weeks later. Lukashenko’s view of who might lead this vast new state on Europe’s doorstep seemed to be, “Why not me?” according to analysts.

He never got the chance. Yeltsin named Vladimir Putin as his successor. Lukashenko went on to rule Belarus for nearly 26 years, jailing opponents and dissidents, clamping down on journalists and earning himself the nickname “Europe’s last dictator.” Progress on the union with Russia stalled.

Relations between the two fraternal states deteriorated into acrimonious sparring in December when they failed to agree on the price of the oil Russia sells to Belarus. Russia cut the supply for several days, forcing Belarus to scrabble for other energy sources before some supplies resumed.

Putin and Lukashenko met in Russia’s Black Sea resort town Sochi on Friday to try to resolve the impasse. The two broke their talks to play ice hockey and were due to meet again Saturday.

As relations have soured, the Trump administration infuriated Russia by reviving contacts with Belarus, apparently seeking to draw it out of Russia’s orbit. U.S. officials have announced plans to reestablish diplomatic relations, which broke off in 2008.

Secretary of State Mike Pompeo visited last week, offering to sell Belarus 100 percent of its oil needs “at a competitive price,” although U.S. oil transported by ship and rail would cost more than that delivered by Russian pipelines. Lukashenko has also courted other powers, including China.

“The time is gone when they shouted that Lukashenko will grab Monomakh’s golden cap,” Lukashenko said sourly last week, referring to the crown once worn by Russian princes.

In 1999, both sides imagined the union very differently. For Lukashenko it was a platform for his ambition, and when that failed, an avenue for cheap oil, which Belarus refined and exported. Russia is Belarus’s biggest market, accounting for more than 40 percent of its exports in the first half of last year, according to the Belarus Foreign Ministry.

In late 1999, after years of humiliation from the West and NATO’s March 1999 expansion into Poland, the Czech Republic and Hungary, Moscow saw the union with Belarus as a chance to push back. The plan for a single currency, a single parliament, a single constitution, court system and other institutions meant that Russia would effectively absorb its small, strategically located neighbor.

The plan never progressed, but Lukashenko benefited in billions in subsidized Russian gas and oil. According to Russian Finance Minister Anton Siluanov, oil and gas subsidies to Belarus cost more than $2 billion a year.

Russia’s 2014 annexation of Crimea and its intervention in Donbass in eastern Ukraine, where war continues, shocked Lukashenko and changed the game.

“For Lukashenko it was a moment of realization that Russia can use military force against its neighbors, even its closest Slavic neighbors, and it scared him,” said Artyom Shraibman, an independent Belarusan political analyst based in the capital Minsk. “We’re seeing his efforts to unfreeze relations with the West after the annexation of Crimea and the war in Donbass.”

Last year, Russia revived work on the union treaty, possibly as a way to extend Putin’s term, which expires in 2024. A union would mean Putin could assume the leadership of a new entity with a whole new constitution. Belarusians took to the streets in protest in December, denouncing “annexation” and Russia’s plans to turn the country into the next Crimea.

Now, Russia is demanding that Belarus pay more for oil and says that by 2024, Belarus will have to pay the world price, a move that would squeeze the Belarusian economy and could harm Lukashenko politically.

“Excuse my language, they bent us over with hydrocarbons, and no one cared. They spat on the union state, and he surely knows that,” said a furious Lukashenko on Jan. 24 in the town of Shklov, apparently referring to Putin. “And we’re quivering, afraid to defend our own country.”

Some of this may be populist rhetoric, with Lukashenko facing an election in August. If he wins, it would be his sixth term. But he has few cards to play in his struggle with Russia.

“I don’t think he will be particularly successful in selling the goods he has always been selling to Russia, which is his loyalty, his geopolitical alliance and his status as one of the last remaining Russian allies,” said Shraibman, predicting a shift to a more pragmatic businesslike relationship.

“There is no integration. There is no unified customs service, so there is no free movement of goods or workers,” said Andrei Suzdaltzev, political analyst at the Higher School of Economics.

“Lukashenko doesn’t need a union. He just needs money and resources from Russia.” Suzdaltzev doubted that the United States would subsidize Belarus to the tune of billions a year, “just because he’s Lukashenko.”