The federal government is expected to announce as early as Thursday that it has chosen Boeing to replace the old military patrol aircraft in a multi-billion dollar deal, according to three sources familiar with the matter.

The decision to proceed with a single-source contract would close the door on Quebec-based business jet manufacturer Bombardier, which was pushing to submit an open bid.

The sources, who were not authorized to speak publicly about the matter, say the cabinet gave the green light last week to purchase 16 P-8A Poseidon reconnaissance aircraft to replace the 50-year-old CP-140 Auroras.

They added, "The Treasury Board held a special meeting last night and approved the contract put forward by a U.S. agency worth $5.9 billion."

The procurement department stated that the ready-to-use reconnaissance aircraft from Boeing is the only available plane that meets the Royal Canadian Air Force's requirements, especially regarding anti-submarine warfare technology.

Bombardier said its alternative—a current prototype—would provide a cheaper and more technologically advanced aircraft made in Canada.