Philadelphia City Council members are in crucial negotiations with developers of the proposed Sixers arena after delaying the start of Wednesday's committee hearing, a spokesman said.

The Sixers have not yet agreed to proposed amendments to a legislative package containing the approvals the team needs to build the $1.3 billion arena.

With a self-imposed deadline for the project's approval fast approaching, the Sixers appear to be at an impasse with City Council over the value of the community benefits agreement included in the deal.