A US federal judge has blocked an order issued by President Trump to deny asylum to migrants crossing the southern US border illegally.

US District Judge Jon Tigar in San Francisco issued the temporary restraining order after hearing arguments by civil rights groups.

Mr Trump signed the order earlier this month in response to the migrant caravan moving towards the border.

He cited national interest concerns but was opposed by civil rights groups.

They brought the San Francisco case saying his decision was illegal.