Saskatchewan Premier Brad Wall. ( IAN KUCERAK/QMI AGENCY)

REGINA - REGINA - Saskatchewan Premier Brad Wall has asked U.S. President Barack Obama to "act swiftly" to approve the Keystone XL Pipeline project.

In a joint letter to Obama, Wall and 10 U.S. governors - including several from states the pipeline would cross - wrote that the project is "fundamentally important to the future economic prosperity of both the United States and Canada."

"We strongly urge you to ... act swiftly to approve the Keystone XL pipeline."

Missing from the letter is a signature from Alberta Premier Alison Redford.

Wall said Redford was aware of the letter and is supportive of it.