Updated

The standoff between the Houston Rockets and rookie forward Royce White escalated further on Sunday, with the team announcing it has suspended the 2012 first-round pick after he refused to accept an assignment to the NBA Developmental League.

White, the 16th overall pick in last June's draft, has yet to play in a game for the Rockets in part due to a complex social anxiety disorder. The 21-year- old and the team have been at odds over how to medically handle his condition, which includes a fear of flying.

White had been assigned to Houston's D-League affiliate, the Rio Grande Valley Vipers, on Dec. 29, but did not report. The Rockets had also previously fined the Iowa State product for missing practices and not attending sessions with a team-assigned physician.

"The Houston Rockets have suspended Royce White effective immediately for refusing to provide services as required by his Uniform Player Contract," Rockets general manager Daryl Morey said in a statement. "We will continue to work with Royce to hopefully come to a resolution."

White lashed out at the decision on his Twitter account on Sunday.

"What's suspending me suppose to do?," he wrote. "I've been away from the team for a month (and) 1/2. Guess we want to give it a title to shift accountability.

"Threat, Fines, Suspension won't deter me. I won't accept illogical health decisions, I will keep asking for safety and health."

During his lone season at Iowa State in 2011-12, White was the only player in the country to lead his team in scoring (13.4 ppg), rebounding (9.3 rpg), assists (5.0 apg), steals (1.2 spg) and blocks (0.9 bpg).