Russia on Friday said French President Emmanuel Macron was made to sit at an enormously long table for his talks with Vladimir Putin because he refused to take a Kremlin-performed Covid test.

The leaders sat at opposite ends of an unusually long table in the Kremlin on Monday, when Macron came to Moscow with a mission to defuse fears of a Russian invasion of Ukraine.

The table drew much ridicule online, and raised more eyebrows when Putin sat at a tiny table with the Kazakh president, a close ally, three days later.

Putin's spokesman Dmitry Peksov said the decision to subject Macron to the huge table was taken after the French leader refused to take a Covid test performed by the Kremlin's medics.

"Talks with some are being held at a long table, the distance (across the table) is about six meters," Peskov said.

"It is linked to the fact that some follow their own rules, they don't cooperate with the host side," he said.

In such cases, he said, the Kremlin has to take "additional sanitary protocol on protecting the health of our president and his guests."

He said the decision on who is subjected to the long table is not political.

"There is no politics here and this in no way interferes with negotiations," Peskov said.

He said that if medics from both sides of diplomatic meetings cooperate, then "Putin communicates with his guests directly, sitting very close and shaking hands."

A source in Macron's entourage told AFP that the French president "did everything as he had to as always when he travels."

Without going into full details, a French presidential official, who asked not to be named, confirmed that the issue has come about over the conditions of the PCR test demanded by the Russian side."

Hungarian Prime Minister Viktor Orban and Iranian President Ebrahim Raisi were also subjected to the long-table diplomacy, made to sit at a distance from Putin when they visited earlier this year.

Putin and Orban also drank champagne while standing at opposite ends of a large carpet in the Kremlin.

The Kremlin has gone to extreme lengths to protect 69-year-old Putin, who is vaccinated with Russia's home-grown Sputnik V, from being infected with Covid.

While social distancing has been lax in many places in Moscow, the long-time Russian leader has been extremely careful with Covid.

Under Russia's current Covid rules, foreigners travelling to Russia are required to take a PCR test before a flight to the country but do not have to take one on arrival.