Turkish jets launched their heaviest assault on Kurdish militants in northern Iraq overnight since air strikes began last week, hours after President Tayyip Erdogan said a peace process had become impossible.

The strikes hit Kurdistan Workers Party (PKK) targets including shelters, depots and caves in six areas, a statement from Prime Minister Ahmet Davutoglu’s office said. A senior official told Reuters it was the biggest assault since the campaign started.

Iraq condemned the air strikes as a “dangerous escalation and an assault on Iraqi sovereignty”, saying it was committed to ensuring militant attacks on Turkey were not carried out from within its territory. […]