WASHINGTON — President Barack Obama and British Prime Minister David Cameron say those who believe violence can be used to muzzle freedom of speech and expression will find the voices they seek to suppress only growing louder.

Obama and Cameron also say they will not be cowed by lone fanatics or terrorist organizations like al-Qaida, the Islamic State group or Boko Haram.

The two leaders are making their pledge to stand together in a joint op-ed in Thursday's editions of The Times of London. It comes a week after terrorist attacks in Paris.

Their article also promotes U.S.-British alliances over the decades and the nations' shared values aimed at economic growth, scientific discovery and national defense.

Obama is scheduled to host Cameron for a working dinner Thursday night at the White House.