In a recent statement, Clearwire Corp. said that its Chairman Craig McCaw is leaving the company – the decision coming at a time when Clearwire has only few days to go for a deadline on critical financial pronouncement by Sprint Nextel, its leading shareholder.

McCaw, a wireless pioneer, informed Clearwire about his departure from the company on December 29; and nominated ex-Clearwire CEO Ben Wolff – McCaw’s trusted right hand man - as his replacement on the board.

The Wall Street observers widely see Wolff as McCaw’s chief negotiator through the latter’s Eagle River Holders investment vehicle, which has a 4 percent share in Clearwire – a company that sells high speed wireless access.

Despite the fact that Clearwire has not given any reason for McCaw’s departure, the company has specified that the decision did not result from “any disagreements with the company on any matters relating to its operations, policies, or practices.”

McCaw’s departure from Clearwire comes at a very crucial juncture, with the company facing a monetary crisis as it requires an additional funding of billions of dollars - even after a $1.3 billion debt offering in December - to complete the construction of its high-speed national network.

Clearwire faces stiff competition from market leader Verizon Wireless, which launched a rival high-speed wireless service in December, as well as MetroPCS, a regional competitor which has already begun offering high-speed services in some markets.