Russian President Vladimir Putin has denied that Russia meddled in the U.S. presidential election, saying the claims lack substance.

Speaking at an economic forum in St. Petersburg, Putin says that the claims contained “nothing concrete, only assumptions.”

He added that IP addresses allegedly belonging to Russian hackers could have been easily rigged and couldn’t stand as evidence.

U.S. intelligence agencies have accused Russia of hacking into Democratic Party emails, helping Donald Trump’s election victory, and the congressional and FBI investigations into the Trump campaign’s ties with Russia have broken the Kremlin’s hopes for a detente with Washington.

“I had never known about anyone meeting anywhere,” said Putin.

The investigations have in large part deal with the Russian ambassador to the U.S. and his contacts with members of the Trump team.

Putin said it’s Sergei Kislyak’s duty to maintain contacts with various people in Washington.

Putin insisted that it was perfectly normal for Kislyak to try to establish contacts and discuss future ties, adding that he hadn’t even started to discuss specifics. He described the focus on Kislyak’s contacts as “catastrophic nonsense.”

Climate accord a framework: Putin

He attributed the accusations of Russian interference to the Democrats’ anger over losing the vote, adding that Trump won because he has been more successful in his campaign.

The Russian president also said that Trump’s promise to negotiate new conditions for the U.S. leaves hope for reaching a compromise before the Paris deal is set to take effect in 2021. Putin added that U.S. participation is essential for the success of global efforts.

U.S. president Barack Obama in December announced sanctions against Russia in the wake of the allegations of election meddling, which included the expulsion of 35 Russian diplomats and the shuttering of two Russian offices in the U.S.

Reports have emerged in recent days that the Trump team will reverse those sanctions.

Putin also sought to assuage concerns caused by Trump’s decision to pull the United States out of the Paris climate accord, calling for a constructive dialogue on efforts needed to curb global warming.

Putin avoided criticizing Trump for the move that has caused international opprobrium.

He underlined the importance of the Paris climate accord, but noted that it’s a framework agreement offering a broad room for manoeuvre for each signatory nation.