A man in his 20s has fallen to his death while abseiling in the Blue Mountains, west of Sydney.

The man fell from Malaita Wall at Katoomba about 8am on Friday.

The group of people he was abseiling with assisted before paramedics arrived, but the man was declared dead at the scene.

An operation was under way to retrieve his body, police said late on Friday.

The man is yet to be formally identified.

The popular rock climbing and abseiling spot is a series of five abseils down two big walls descending into the Katoomba valley.

While it’s unclear which wall the man fell from, the highest wall is 45m.