Government leaders from around the world have congratulated Joe Biden for his win in the U.S. presidential election.

However, Russia President Vladimir Putin has yet to issue a statement. Political experts said that this could foreshadow tense years ahead.

With Putin still mum about Biden's win, his political opponent Alexey Navalny has taken the opportunity to express his support for the new U.S. administration. Navalny also poked at Putin's administration during his congratulatory remark, saying that the privilege of "free and fair elections" is sadly not present in all countries.

"Congratulations to @JoeBiden and @KamalaHarris on the victory and to the Americans on defining the new leadership in a free and fair election. This is a privilege which is not available to all countries. Looking forward to the new level of cooperation between Russia and the U.S.," Navalny said in a post on Twitter.

In August, Navalny was poisoned by a nerve agent. After he collapsed on a plane, Navalny was taken to Serbia where doctors found out that he was poisoned.  Navalny had accused Putin and his administration of being involved. Putin has denied the allegations.

Giving his congratulations to the new administration before an official reaction from the Kremlin is expected to further increase tensions between Russia and both Navalny's party and the U.S. Putin has been open about his support for the Trump administration. In 2016, Russia was accused of interfering with the elections, with some saying that they had played a major part in Trump becoming president.

Since he was elected, Trump has taken a much softer approach to the country's relations with Russia. Biden is expected to take a much tougher stance. During his campaign, Biden criticized Trump for embracing too many autocrats, including Vladimir Putin.

Apart from Navalny, leaders from major countries around the world have expressed their congratulations on Biden's win. This included official congratulatory messages from British Prime Minister Boris Johnson, German Chancellor Angela Merkel and French President Emmanuel Macron.