81-year-old Senator John McCain said that "an American president does not lead the Free World by congratulating dictators on winning sham elections."
"And by doing so with Vladimir Putin, President Trump insulted every Russian citizen who was denied the right to vote in a free and fair election to determine their country's future," McCain added.
However, Twitter users were quick to react to McCain's verbal attack against Trump, with some urging the senator "to lean respect" and consider resigning.
McCain's remarks came after media reports said that in a telephone conversation on Tuesday, US President Donald Trump congratulated Vladimir Putin on his win in the March 18 presidential elections in Russia.
Additionally, the two discussed an array of pressing international issues, including North Korea, Syria, Ukraine and the development of Russian-US relations.
According to the Washington Post newspaper, citing officials familiar with the situation, Trump has ignored the specific warnings of his security advisers to avoid congratulating Putin on his victory in Sunday's election. Trump’s briefing materials read "DO NOT CONGRATULATE," the US officials told the WP, referring to the call between the two leaders.
Moreover, the US president opted not to condemn Russia’s alleged involvement in the case of ex-spy Sergei Skripal's poisoning during the Putin call despite the contrary recommendations of his team, according to the newspaper. Moscow has denounced the claims of alleged Russia's involvement in the case, with Putin calling the allegations "nonsense."
"We are ready to cooperate, we immediately said this, we are ready to take part in the necessary investigations, but for this we need to have an interest on the other side, we do not see it yet," Putin said on Sunday.