LAS VEGAS (AP) — Company and project officials are estimating the costs of a spherical entertainment venue under construction on the Las Vegas Strip at between $1.2 billion and $1.7 billion.

Madison Square Garden Co. President Andrew Lustgarten disclosed cost projections Tuesday along with quarterly company earnings.

The 18,000-seat arena, called MSG Sphere, is a partnership between MSG and Las Vegas Sands, the owner of the adjacent Venetian and Palazzo resorts.

The Las Vegas Review-Journal reports the company and general contractor AECOM are negotiating a final cost.

It could be more than four times the $375 million it took to build T-Mobile Arena, which opened in 2016 about 4 miles (6.4 kilometers) down the Strip.

MSG Sphere is scheduled to open in 2021 with a huge interior wrap-around LED screen and immersive audience experience technology.