Two more US states have confirmed they are joining a legal challenge aiming to overturn Donald Trump's revised travel ban.

Attorneys for both Washington State and Massachusetts have confirmed they are adding themselves to the legal action brought by Hawaii.

There were also reports that Oregon and New York were set to join the case, which could yet derail Mr Trump's fresh attempt to close the country's border to many refugees and migrants.

The current order affects visitors, refugees and migrants from six Muslim-majority countries: Iran, Syria, Somalia, Sudan, Yemen and Libya.

He says that the order is necessary to protect the US from terrorism, while critics say it is ill-conceived and discriminatory.

Hawaii's lawsuit said that the new order is "illegal" and would harm the state's Muslim population as well as potentially having a knock-on effect on its residents, businesses and schools.

Mr Trump signed his new travel ban after his initial order was suspended by a judge pending a full hearing on whether it was unconstitutional.