A record 252-member expedition from Japan, China and Nepal perched on the icy slopes of Mount Everest Wednesday, poised to make its final steps to the highest point on Earth.

Twelve members of the international expedition are scheduled to assault the peak Thursday in two groups coming from opposite sides of the mountain, which straddles the Nepal-Tibet border.After reaching the peak, six of the climbers are to descend on the side opposite their approach - a so-called "cross-traverse" maneuver that has never been attempted.

Ang Phurba, a Nepalese climber, was the last expedition member to get in place for the summit assault. The Nepal Mountaineering Association, co-organizer of the expedition, said he reached a point about 27,900 feet up the Nepal side of the 29,029-foot mountain.

The Association said Ang, 28, was being followed by five other climbers on the south side and that six climbers on the north side were already at their final camp site preparing for the early morning assault on the summit.