Sept 20 (Reuters) - U.S. regulators on Friday issued a long-awaited rule on Friday requiring companies to include codes on medical devices that will allow the Food and Drug Administration to track devices, monitor them for safety and issue recalls when needed.

The FDA will enter the unique device identifier, or UDI codes, into a database that the agency will maintain as a publicly searchable reference catalogue.

"A consistent and clear way to identify medical devices will result in more reliable data on how medical devices are used," said Dr. Jeffrey Shuren, director of the FDA's medical device division, in a statement.

The FDA plans to phase in the UDI system, focusing first on medical devices that carry the greatest risk to patients such as pacemakers, defibrillators, heart pumps and artificial joints. Many low-risk devices will be exempt from some or all of the requirements.

The FDA said medical device records will have to include the UDI code. The rule also establishes accreditation requirements for agencies that may operate systems for issuing UDI codes.