President Barack Obama has offered his most direct remarks to date about any link between Islam and terrorism.

Addressing a White House summit on countering violent extremism, the president said that Muslims in the U.S. and around the world have a responsibility to fight a misconception that terrorist groups like the Islamic State speak for them.

Said Obama: ``We are not at war with Islam. We are at war with people who have perverted Islam.''

For weeks, the White House has sidestepped the question of whether deadly terror attacks in Paris and other Western cities amounted to ``Islamic extremism.'' But in his latest remarks, Obama said some in Muslim communities have bought into the notion that Islam is incompatible with tolerance and modern life.

The president said all individuals have a duty to ``speak up very clearly'' in opposition to violence against innocent people.