"The coalition urges civilians to evacuate areas near positions held by the Huthis," read a statement published by Saudi Arabia's state-run Al-Ekhbariya TV.
"We ask civilians to remain at least 500 metres away from Huthi military vehicles and gatherings."
Clashes erupted in Sanaa last week between forces loyal to ex-president Ali Abdullah Saleh and the Shiite Huthi rebels, who together seized control of Sanaa from Yemen's Saudi-backed government three years ago.
On Saturday, Saleh announced he was open to talks with Saudi Arabia and its allies, dealing a major blow to his fraught alliance with the Huthis.
Yemen's internationally recognised president, Abedrabbo Mansour Hadi, has ordered his forces to retake control of Sanaa, an official from his office told AFP Monday.
The official called it an operation to restore Sanaa's "Arabism" -- a jab at the Huthi rebels' proximity to Iran.