Increased US air strikes on Islamic State (Isis) targets do not constitute a change in strategy, but rather are meant to deny the group a "safe haven", the White House said on 6 July.

Over the weekend (4-5 July) US-led forces carried out some of the heaviest air strikes of the conflict against the IS de facto capital of Raqqa in coordination with Kurdish (YPG) fighters.

Josh Earnest, the White House Press Secretary, said on Monday 6 July that the air strikes had sent a message to the Islamic State that they could not hide.

"It's my understanding that many of the air strikes that were taken over the weekend around Raqqa were an effort to try to deny IS a safe haven. We know that many ISIL leaders are operating out of Raqqa or that immediate area and I think this sends a pretty clear signal to them that's not a safe place for them to be," he said.

The White House also sought to counter speculation that the increase in air strikes constituted a change in policy.

"I would not read that increased pace of air strikes over the weekend as a significant change in our strategy. If anything it would be the logical continuation of a strategy that would reflect our effort to try to support those fighters who are acting on the ground," said Press Secretary Josh Earnest.

The Syrian Observatory for Human Rights, which reports on the war, said IS forces had taken Ain Issa and areas around it some 30 miles north of Raqqa city.

The monitor said at least 37 IS fighters were killed and scores wounded in air strikes by the coalition and in clashes with Kurdish militia in the last 24 hours in north-eastern Syria.