WASHINGTON — A national system that will send emergency alerts to cell phones is set to begin in Washington and New York City by the end of the year.

The Federal Communications Commission and Federal Emergency Management Agency said Monday the system will warn people about terrorist attacks, natural disasters or other emergencies.

Starting next year all new cell phones will be required to have a chip that receives the alerts. Some smartphones already have the technology. People can opt out of certain alerts, such as the Amber alerts for missing children.

The alert system will send the emergency messages even if other cell phone voice or text services aren’t working. It is expected to be in place in cities across the country by the end of next year.