WASHINGTON - US President Donald Trump on Wednesday will order a review of national monuments created over the past 20 years with an aim toward rescinding or resizing some of them - part of a broader push to reopen areas to drilling, mining and other development.The move comes as Trump seeks to reverse a slew of environmental protections ushered in by former President Barack Obama that he said were hobbling economic growth - an agenda that is cheering industry but enraging conservationists.Interior Secretary Ryan Zinke told reporters on Tuesday Trump's executive order would require him to conduct the review of around 30 national monuments and recommend which designations should be lifted or resized over the coming months. He said he would seek feedback from Congressional delegations, governors and local stakeholders before making his recommendations."I am not going to predispose what the outcome is going to be," Zinke said. Rescinding or altering a national monument designation would be new ground for the government, he said."It is untested, as you know, whether the president can do that," Zinke said.The monuments covered by the review will range from the Grand Staircase in Utah created by President Bill Clinton in 1996 to the Bears Ears monuments created by President Barack Obama in December 2016 in the same state, covering millions of acres of land overlying minerals, oil and gas.