Biden has extensive experience working with Russia thanks to visits to the Soviet Union to discuss arms control and that will also be his duty when entering the White House.

In 1988, when the Cold War was coming to an end, Sen. Joe Biden visited the Soviet Union to negotiate arms control.

"Would you mind if my son, Hunter Biden, come in here and listen? My child is interested in international affairs and diplomacy," he said, according to Victor Prokofiev, translator of the Soviet Foreign Ministry.

A photo from the meeting shows Biden's son sitting at the head of the table as his father and Andrei Gromyko, chairman of the Supreme Soviet Presidium, discuss ratification of the Intermediate-Range Nuclear Forces (INF) Treaty.

"It's incredible," Prokofiev said.

Upon entering the White House next month, Joe Biden has the inventory of nearly half a century of foreign policy experience, making him one of the most seasoned envoys ever elected president.

Biden bragged about his wealth of experience in his 2007 memoir. Biden said that he sat across from Soviet President Leonid Brezhnev for a short time in the Kremlin in 1979, before negotiating with the Prime Minister of the Soviet Union.

However, Andrei Kozovoi, a historian at Lille University and author of an upcoming biography of Brezhnev, said Brezhnev never mentioned meeting these US senators in his diary.

"Brezhnev didn't attend any of the meetings that I was in and I attended all the US delegation meetings during that trip," said Bradley.

Biden's other statements about overseas trips have also raised questions.

The arrival of the Biden story Biden's Brezhnev appearance made Biden appear "bigger in size" at the time he was a young senator.

But during those travels, Biden has cultivated his signature stubborn style.

That is the role he will assume next month with Putin, when the New Strategic Arms Reduction Treaty (New START), an agreement he pushed for the Senate to pass in 2010 as vice president,

However, Biden is also remembered in Russia as a supporter of bilateral tensions, seeking to close the gap between Moscow and Washington even as relations collapsed in the early 1980s.

"If we had the Biden of the 1970s and 1980s at the White House, people wouldn't worry," says Sergey Karaganov, a famous foreign policy expert who played a minor role in organizing the trips Biden took.

He recalled the impression Biden had left at the time: "American, handsome, a more traditionally left-wing politician."

A 1979 Biden televised interview was mentioned a lot in Russia after he was re-elected as senator.

The Soviet army's deployment in Afghanistan in 1980 pushed relations between the White House and the Kremlin into a deep freezing state.

In 1988, Biden returned to the same delegation and brought his son with him to discuss the ratification of the INF with Gromyko.

About 20 years later, Biden made another important visit to Moscow, at a time when Putin had "dominated" Russian politics for a decade and the bilateral relationship worsened despite being restarted.

But, says Bradley, decades of policy experience still work.

In 2011, Biden said that he once told Putin directly: "Prime Minister, I am looking into your eyes, I don't think you have a soul".

"We understand each other," Putin replied, as told by Biden.

Biden also told opposition leaders at the time that Putin should not run for a third term.

Some Russian analysts believe that Biden has crossed the "red line".