President Trump has signed an executive order that could open large parts of the Pacific, Arctic and Atlantic oceans to new oil and gas drilling, creating yet another clash with California, where leaders are vowing they will do everything in their power to block new drilling off the state’s shores. 

Trump’s move, which is certain to face legal and political challenges, could undo a plan finalized late in President Obama’s second term that sought to limit fossil fuel development and fight climate change by not including new drilling leases off the coast of California or Alaska during the current five-year federal offshore plan, which extends through 2022.

Many leaders in California have long sought a permanent ban on new leasing offshore, and they reacted swiftly to the possibility that drilling could expand.

President Trump is scheduled to head to Atlanta on Friday afternoon to bask in the adulation of one of his friendliest audiences -- the National Rifle Assn. -- part of an effort to excite supporters and convey a sense of accomplishment ahead of the 100-day mark of his presidency.

The group, which is holding its annual leadership forum, backed Trump nearly a year ago, sooner and more forcefully than other major conservative organizations.

The organization called the Supreme Court vacancy the election's most important issue, and Trump has not disappointed on that front. He and his advisors tout the selection and approval of Neil M. Gorsuch as Trump's top legislative accomplishment ahead of Saturday's 100-day mark.

The House won't vote on Republican legislation that would scuttle much of President Obama's healthcare law until at least next week, a GOP leader said late Thursday. The decision deals a setback to the White House, which has pressured congressional Republicans to pass the bill by Saturday, President Trump's 100th day in office.

“As soon as we have the votes, we'll vote on it,” House Majority Leader Kevin McCarthy (R-Bakersfield) told reporters after leaving a meeting of the House GOP leadership that lasted nearly two hours. He said the vote would not occur Friday or Saturday.

White House and Republican leaders had labored all day to wring votes out of resistant moderate GOP lawmakers for the healthcare measure. But they remained shy of the number they'd need to revive a Republican bill that was withdrawn last month for lack of support, and it was uncertain when a vote on the revamped legislation might occur.

Liberal sanctuary cities in California and elsewhere may well win their legal battle against President Trump thanks to Supreme Court rulings once heralded by conservatives, including a 2012 opinion that shielded red states from President Obama’s plans to expand Medicaid coverage for low-income Americans.

On Tuesday, a federal judge in San Francisco temporarily blocked enforcement of Trump’s sanctuary city executive order, resting his ruling on high court decisions that protected states and localities from federal meddling.

The Senate on Thursday confirmed Alex Acosta as secretary of Labor, filling out President Trump's Cabinet as he approaches his 100th day in office.

The 60-38 vote confirms Acosta to the post. Once sworn in as the nation's 27th secretary of Labor, the son of Cuban immigrants will lead a sprawling agency that enforces more than 180 federal laws covering about 10 million employers and 125 million workers.

Acosta has been a federal prosecutor, a civil rights chief at the Justice Department and a member of the National Labor Relations Board. He will arrive at the top post with relatively little clear record on some of the top issues facing the administration over key pocketbook issues, such as whether to expand the pool of American workers eligible for overtime pay.

President Trump on Thursday handed over to Argentine President Mauricio Macri a trove of declassified documents from the South American nation's military-led "dirty war."

The documents contain hundreds of pages of presidential notes, CIA memos, FBI reports and other records that in many cases chronicle human rights atrocities committed by Argentine military officials when they ruled the country from 1976 to 1983.

The dirty war was backed at least tacitly by U.S. officials during that era, historians say. An estimated 30,000 dissidents were killed, and untold thousands of children were kidnapped.

Congress hopes to avoid a government shutdown by swiftly approving a stopgap spending bill Friday to allow negotiations to continue for another week on a longer-term funding deal.

Progress continued in the talks to finalize the must-pass legislation and avert a crisis as President Trump prepares to mark his first 100 days in office.

The deal is likely to include a sizable boost of about $15 billion in defense spending supported by both parties, about half the amount Trump was seeking for the rest of the 2017 fiscal year that ends Sept. 30.

To read the polls and hear the pundits, President Trump’s first 100 days have been an utter disaster, ranking among the worst in history. But that’s not how Karen Malady sees it.

The 59-year-old accountant was drawn to Trump’s unconventional candidacy from the start, unlike other Republicans who came around reluctantly. She saw him as an outsider and disrupter, and his first months in office proved her right, she said, about that and other things too.

Like no matter how much he tries, some won’t ever give Trump a fair shake.

The Pentagon said two American troops were killed and a third wounded Wednesday night during a raid against Islamic State’s affiliate in eastern Afghanistan, near the site where an 11-ton U.S. bomb was dropped earlier this month.

The service members were conducting an operation alongside Afghan forces in Nangarhar province, where a U.S.-backed offensive is underway against Islamic State-Khorasan, or ISIS-K. Khorasan is the historic name for a region that encompassed parts of modern-day Afghanistan.

"The fight against ISIS-K is important for the world, but sadly, it is not without sacrifice,” said Gen. John W. Nicholson Jr., commander of U.S. forces in Afghanistan. “On behalf of all U.S. forces and our coalition partners, I offer our deepest sympathies to the families, friends, and fellow service members of our fallen comrades.”