According to Mihkelson, it is generally diplomatic practice for neighboring countries, regardless of how complicated their relations are, to demonstrate respect for one another with such gestures.

"It has not been an easy decision for previous Estonian presidents to make either," Mihkelson told ERR on Wednesday. "At the same time, we must not forget that there are many reasons why such a congratulatory message is very delicate in nature."

For one thing, he noted that Russia is not a democratic state, and election there are neither honest nor free. "Unfortunately, a number of potential candidates have been killed recently, such as Boris Nemtsov, or artificially excluded from the elections, such as Alexei Navalny," he said.

Also, he continued, Russia is continuing aggression toward Ukraine, getting involved in the internal affairs of other countries, and threatening both the EU and NATO, the last of which are pillars of Estonian security.

The committee chairman noted that Russia has strayed dangerously far from international law and eschewed the fulfillment of obligations it had taken on itself. Referring to the nerve gas attack in Salisbury, U.K. earlier this month, he found that the use of a chemical weapon on NATO territory was a clear warning sign that cannot go unanswered.

Mihkelson also pointed out that Putin's election campaign directly slighted Estonia and President Lennart Meri, as a promotional film referred to an incident that took place in 1994 in Hamburg. Using symbolic language, Putin described how, upon hearing Meri talk about the Soviet occupation, he got up from among the audience and left the room, slamming the door behind him. Mihkelson noted that Putin only recently said that if he could, he would reverse the fall of the Soviet Union.

U.S. president criticized for congratulating Putin

Mihkelson also retweeted a rebuke of U.S. President Donald Trump's congratulatory message to Putin posted by Sen. John McCain (R-Ariz.):

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. https://t.co/lcQTBi7CA1

— John McCain (@SenJohnMcCain) March 20, 2018

Baltic heads of state differ in approach

Although the decision was delayed until Wednesday, Latvian President Raimonds Vējonis ultimately decided to send his congratulations to Putin.

Lithuanian President Dalia Grybauskaitė, however, chose not to congratulate the re-elected Russian president.