Jorge Guerrero/AFP via Getty Images Spain: post-Brexit UK should drop Gibraltar With thousands commuting from Gibraltar to Spain every day, García-Margallo y Marfil says Britain should cede the territory.

Spain's Foreign Minister José García-Margallo y Marfil proposed shared sovereignty of Gibraltar, to be followed by its "restitution" to Spain, after the British territory voted overwhelmingly to remain in the EU while the U.K. overall voted to leave.

"Our formula ... is British-Spanish co-sovereignty for a determined period of time, which after that time has elapsed, will head towards the restitution of Gibraltar to Spanish sovereignty," García-Margallo told Spanish radio on Friday, AFP reports.

Gibraltar, a former Spanish territory which was ceded to Britain in 1713, heavily relies on Spain for its economy, with over 12,000 people commuting across the border every day.

"It is now a bilateral issue that will be negotiated exclusively between the U.K. and Spain," García-Margallo said, AFP reports. The Spanish Foreign Minister added a solution was necessary for Gibraltar to maintain its position in the EU's single market.

Gibraltar's chief minister Fabian Picardo called for unity and calm on Twitter.

We have surpassed greater challenges. It is time for unity, for calm & for rational thinking. Together & united we will continue to prosper. — Fabian Picardo (@FabianPicardo) June 24, 2016