Clearwire said in a Monday regulatory filing that it may delay portions of its TD-LTE network.

The company must roll out 5,000 TD-LTE cell sites by the end of next June to get a prepayment from Sprint for access to the network, which it plans to use to supplement its own FDD-LTE service.

"However, our agreements with Sprint also provide flexibility to modify the pace of our LTE deployment and remain eligible for the full amount of LTE prepayments from Sprint," Clearwire said in a SEC document. "As such, in order to better align our capital expenditures with the receipt of expected LTE revenues, we are currently evaluating our plans and may elect to delay a portion of our deployment schedule accordingly."

Clearwire did not specify whether the potential delays would affect the first phase of its LTE deployment.

The TD-LTE network will eventually overlay 8,000 WiMAX cell sites after the first phase of construction is complete.The service is scheduled to be deployed in high-traffic areas where wholesale customers need to offload traffic from their own LTE networks.

Clearwire also disclosed that Comcast had taken steps that would allow it to divest its stake in Clearwire. Comcast has converted its Class B stock into Class A stock, which it can sell on the open market.

Comcast has not notified Clearwire of its intent to sell the stock, the company said. The news of Comcast's changes to its shares comes shortly after Time Warner Cable sold off its 7.8 percent stake in Clearwire at a significant loss.

Clearwire said it needs to expand its wholesale business with new customers and increased sales to existing wholesale customers, which include Sprint, Leap Wireless International, EarthLink, Simplexity, FreedomPop and Jolt Mobile.

It has enough cash on hand to operate its business through the end of June 2013, but "we may be required to raise additional capital during the period to fund our current business if our business fails to perform as we expect, or if we incur unforeseen expenses."