The British government is poised to accept 15,000 Syrian refugees and hopes next month to get backing for air strikes against Islamic State jihadists, the Sunday Times reported.

Prime Minister David Cameron has been under pressure internationally and domestically to address the refugee crisis.

On Thursday, he said he was "deeply moved" by images of three-year-old Syrian toddler Aylan Kurdi, found dead on a Turkish beach.

Cameron now intends to expand Britain's vulnerable persons relocation programme, take in around 15,000 refugees and launch military action against people traffickers, the report said.

He also hopes to persuade MPs in the opposition Labour Party to back air strikes in Syria in a vote early next month, it said.

The paper previously reported that there was an option to directly accept refugees from UN camps on the Syrian border.

Britain has accepted 216 Syrian refugees under a special government scheme over the past year and around 5,000 Syrians have been granted asylum since the conflict there broke out in 2011 -- far fewer than countries like France, Germany and Sweden.

Britain has also opted out of a quota system for relocating asylum seekers within the European Union despite growing calls in the EU for fairer distribution.

More than four million Syrians have fled the war.

Cameron gained support for military action against Syria from an unusual source on Sunday -- former Archbishop of Canterbury, the leader of the world's Anglicans, George Carey.

Britain should help "crush" the Islamic State and "air strikes" may be needed, Carey said.

"I do not consider it enough to send aid to refugee camps in the Middle East. Rather, there must be renewed military and diplomatic efforts to crush the twin menaces of Islamic State and al-Qaeda once and for all," he wrote in the Sunday Telegraph.