17 US states file lawsuit to block Obama's immigration order

Say Obama's move will increase unauthorised immigration, make southern border less secure

A coalition of 17 US states led by Texas have filed a federal lawsuit aiming to block the implementation of President Barack Obama's executive order shielding some five million undocumented immigrants from deportation.

"The president is abdicating his responsibility to faithfully enforce laws that were duly enacted by Congress and attempting to rewrite immigration laws, which he has no authority to do," Texas Attorney General Greg Abbott said Wednesday.

Abbott, who will become governor of the Lone Star state in January, has argued that Obama's measures will encourage more unauthorised immigration and make the southern border less secure.

Joining Texas in the suit are Alabama, Georgia, Idaho, Indiana, Kansas, Louisiana, Maine, Mississippi, Montana, Nebraska, North Carolina, South Carolina, South Dakota, Utah, West Virginia and Wisconsin.

Arizona's Sheriff Joe Arpaio, known for his tough line towards undocumented migrants, filed a private suit against Obama's executive order the day after the president detailed his plan.