After completing some record-breaking swims in Antarctica, Lewis Pugh flew to Moscow to discuss ocean conservation.
The UK athlete and campaigner wanted to meet the Russian Minster of Defence to discuss the creation of a new marine reserve around the Ross Sea.
Sergey Shoygu is also the president of the Russian Geographical Society.
Despite international tensions, Mr Pugh believes that their conversation could help the world to reach an agreement on the proposed protected zone.
The Ross Sea covers that slice of Antarctica claimed by New Zealand, and from which teams associated with Scott, Shackleton and Amundsen all mounted polar forays.
The sea is one of the last regions in Earth's oceans still regarded as near-pristine and unaffected by human activities. But there is deadlock over giving it a special designation.
Speaking of his Russian encounter, Mr Pugh told the BBC: "This is the first time that Antarctica has been discussed at this level.
"Until now, it hasn't got this far. They indicated that there is an appetite for dialogue and for peace.
"When you take off your clothes, there are no barriers. You can talk person to person."
However, Mr Pugh, who is the UN Environment Programme Patron of the Oceans, warned that it would be a lengthy process, particularly given the international disagreements over Ukraine.
"The relationship between the US and Russia and the United Kingdom and Russia is very strained. This is the most serious crisis that these parties have faced since the Cold War. There are no bilaterals happening at this stage."
As part of a series of Antarctic swims, this month Mr Pugh swam further south than anyone has swum before. Breaking his own record, he said that the Bay of Whales in the Ross Sea was "the most terrifying place" that he had ever swum. The average sea temperature was -1C , with an air temperature of -37C.
The Ross Sea Marine Protected Area (MPA) has been discussed for the last four years and it has failed four times. The last proposal was vetoed by Russia and China.
It would be the size of the UK, Germany and France put together, and needs 24 countries and the EU all to agree.
Mr Pugh said: "If you look at the 1959 Antarctic Treaty, this was concluded at the height of cold war. All of the parties set aside land, the continent, as a place of peace and science.
"I hope that Antarctica could be used as a bridge, as a place where we could try to find common ground. My hope is that this would ripple northwards."