The main contractors for Apple's "Spaceship" Campus 2, Skanska and DPR, are no longer part of the project.

The Cupertino City Council gave Apple the green light to build its spaceship-like headquarters back in 2013, and Skanska and DPR won the bid in a joint venture to be Apple's main contractors.

Midway through the construction of its second campus, Apple has now reportedly cut ties with both Skanska and DPR.

"Skanska and its joint venture partner were not able to come to an agreement with the client during negotiations for the revised scope of work," explains a press release from Skanska. "Accordingly, the client has elected to terminate the contract for its own convenience."

The "client" Skanska refers to in this announcement is Apple, but Skanska was not allowed to explicitly say who it was working for.

Skanska and DPR "will transition completely off the project in the next several weeks," further reveals an internal email obtained by the Silicon Valley Business Journal.

Considering the stage of the project, switching contractors now will likely have a significant impact on Apple and its Spaceship headquarters, delaying the project and increasing the costs.

Apple already retained another company called Rudolph & Sletten to handle the interior build-out of its Campus 2, while Skanska and DPR were charged with the exterior.

With both Skanska and DPR now out of the equation, the Silicon Valley Business Journal believes that Apple will collaborate with Atlanta firm Holder Constructions to finish the exterior build-out of its second headquarters. The same company previously worked on Apple's data center in North Carolina and is also working on the mechanical, electrical and plumbing systems of the Cupertino Spaceship project. If the Journal turns out to be accurate, Holder Construction may take on the exterior as well.

Nevertheless, changing contractors at this point will surely delay work at the Spaceship-like Campus 2, possibly dragging it into 2017. Apple is already behind schedule, as it wanted to complete the Spaceship headquarters in 2015.

It remains to be seen how Apple will choose to move forward and with which contractors, but the shift will take a toll on the development of the Spaceship campus, which is already behind and over budget.