Iraq crisis: Obama to set out 'US offensive against IS'

US President Barack Obama is to make a speech on Wednesday to set out his "game plan" against Islamic State militants.

Mr Obama has been criticised for failing to outline a strategy, but he told NBC TV the US would degrade IS, shrink their territory and "defeat them".

Meanwhile, the Arab League has vowed to take "all necessary measures" against IS, which has seized a huge amount of territory from Iraq and Syria.

Peter Dobbie reports.