It's a friendly tradition for one world leader to congratulate another on winning reelection. But when it comes to Russia and its president, Vladimir Putin, the situation is more complicated.

Not only have election monitors cast doubt about the legitimacy of Russian elections, but Putin has been linked to election interference in the United States and other countries. Then there is the apparent attempt to assassination an ex-Russian spy and his daughter using a powerful nerve agent in Britain earlier this month.

Despite all this, President Trump called Putin to congratulate him on Tuesday.

The Washington Post reported that national security advisers to the president had advised Trump against congratulating his Russian counterpart — even handing him briefing materials that contained a message “DO NOT CONGRATULATE.” Trump appeared to either ignore the advice or not read the memo.

After the Kremlin disclosed the call, Trump confirmed that he had made it and told reporters of Putin: “We’ll probably be meeting in the not-too-distant future.”

Trump was not alone in congratulating Putin. According to the Kremlin, the Russian leader received calls from a wide variety of world leaders, including French President Emmanuel Macron, Turkish President Recep Tayyip Erdogan, Chinese President Xi Jinping, Indian Prime Minister Narendra Modi and Japanese Prime Minister Shinzo Abe.

A number of other world leaders have also sent notes of congratulation, the Kremlin said, including German Chancellor Angela Merkel, North Korean leader Kim Jong Un and Syrian President Bashar al-Assad.

One prominent name not on the list of well-wishers, however, was British Prime Minister Theresa May, who is currently locked in a diplomatic standoff with Putin over the poisoning of Sergei Skripal and his daughter, Yulia, in Salisbury, England.

A spokesman for May told reporters that the British leader would offer a statement on the Russian election after it has been assessed by election observers from the Organization for Security and Cooperation in Europe.

Other American allies in Europe have held back, too. There is no account from either side of a message to Putin from Dutch Prime Minister Mark Rutte, whose government is at odds with Moscow over the shooting down of Malaysia Airlines Flight 17 over Ukraine in 2014. The attack left 193 Dutch nationals dead.

There has been no public announcement of a message from Swedish Prime Minister Stefan Löfven, either. In fact, Swedish Foreign Minister Margot Wallström said Monday that the Russian vote was “in many ways a rigged election.”

In Eastern Europe, Lithuanian President Dalia Grybauskaite declined to congratulated Putin, while local media reported that Latvia's president, Raimonds Vejonis, had not made a decision on the matter. Ukrainian President Petro Poroshenko did not congratulate Putin for his election win but instead released a statement that criticized Russia for its decision to hold voting in Crimea — territory that was annexed from Ukraine in 2014.

The Kremlin may have overstated the nature of some of the calls Putin received, too. In France, the Elysee Palace offered a notably different account of Macron's phone call. The French president's office released a readout of the call on Monday that made no reference to congratulations but instead wished Russia the best in its “modernization.”

The Elysee statement also referred to Russian involvement in the conflicts in Ukraine and Syria, as well as the poisoning of Skripal. The Post reported Tuesday that Trump had also been advised to raise the Skripal poisoning with Putin, but he did not.

In calling Putin, Trump was following precedent. In 2012, President Barack Obama called Putin on the Friday after the election, which occurred the previous Sunday. In 2008, George W. Bush called Dmitry Medvedev two days after the vote, but U.S. accounts of the call did not include any note of congratulations.

Kremlin spokesman Dmitry Peskov told reporters Tuesday that Russia would not have taken it as an act of hostility if Trump had not called. “We don’t consider this an unfriendly act. As you know, President Putin is open to normalizing relations,” Peskov said, according to Tass news agency.

Many world leaders might be unable to offer congratulations to Putin because of their schedules, Peskov added. “There is no reason to make a mountain out of a mole hill about anything here. Lastly, there is a good old saying: ‘Sleep on it,’ ” Peskov said.

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