Boric, accompanied by two government ministers and three military commanders, was expected to arrive at Amundsen-Scott South Pole Station, a US research base, at 1930 GMT, his office said in a statement.

The Chilean leader was to spend about two hours at the US outpost, in one of the planet's most remote and hostile zones.

Boric began his voyage early in the day from Punta Arenas, in southern Chile, reaching the Glaciar Union base, in Antarctica, aboard a Hercules C-130 military transport plane.

He is only the third world leader to attempt a South Pole visit, according to his office.

In 2007, then New Zealand prime minister Helen Clark made the trip, followed in 2011 by former Norwegian prime minister Jens Stoltenberg.

Stoltenberg was commemorating the 100th anniversary of Norwegian explorer Roald Amundsen's trip to the South Pole in December 1911.

Boric's visit comes "at an important moment for Chile's scientific endeavors in the region," his office said.

In the past, Chile has concentrated its research in the northern part of Antarctica, but the South American country is hoping to expand its efforts to the Bellingshausen and Weddell Seas, according to the statement from the presidency.

During the 20th century, countries like Chile, France, the United States, Britain, Argentina and Japan set up research stations in Antarctica, both for scientific research and to establish a presence in the forbidding region.

Since 1961, activities in the region are governed by the Antarctic Treaty, which seeks to shield the continent and its surrounding seas from geopolitical rivalries.