Kremlin critics and Russian bloggers on Tuesday mercilessly mocked President Dmitry Medvedev after microphones picked up him promising to "transmit" a message from Barack Obama to Vladimir Putin.

"I understand. I will transmit this information to Vladimir," Medvedev was heard telling Obama in English in a "hot-mike" exchange on the sidelines of a summit in South Korea that has already caused a storm in the United States.

Medvedev was responding to a vow by Obama that the United States will be more flexible on some bilateral issues such as missile defence once, as he expects, he is re-elected as US president in November elections.

Russian bloggers immediately circulated Medvedev"s phrase on Twitter, ridiculing Medvedev for his apparent admission that all information needs to go through the all-powerful Russian number one Putin.

"Today, let"s all respond to every tweet: "I will transmit this to Vladimir"," tweeted opposition movement leader Alexei Navalny.

"Vladimiru", the Russian for "to Vladimir" became a worldwide Twitter trend in a matter of a couple of hours Tuesday morning as bloggers used it as a universal response to any sort of statement or demand.

Medvedev is already widely seen as a lame duck head of state as he will cede the Kremlin on May 7 after four years in power to president-elect Putin, even though he is expected to become prime minister.

Bloggers circulated an image of Putin answering his cell phone in the country side, with the caption saying "Hello, I am Vladimir. Did anyone transmit anything to me?"

Medvedev, who was picked as his successor by Putin in 2008, was never able to shake off his reputation as a president who is not entirely first in command.

Last September similar footage made its way onto the Internet of Medvedev pushing finance minister Alexei Kudrin to quit at a government meeting, to which Kudrin replied "I will consult with the prime minister."