President Barack Obama plans to ask for an increase in military spending in a proposed budget for 2016, with a request for $585 billion that would exceed funding caps mandated by Congress, officials said Wednesday.

The budget proposal for the Pentagon would provide for a hike in spending on weapons, research and maintenance, which had been scaled back under automatic budget cuts in recent years, officials told AFP.

Recent satellite images suggest North Korea may be about to restart the nuclear reactor seen as its main source of weapons-grade plutonium, a U.S. think-tank said Thursday.

When fully operational, the five-megawatt reactor at the Yongbyon nuclear complex is capable of producing around six kilos (13 pounds) of plutonium a year -- enough for one nuclear bomb, experts say.

The U.S. military said Wednesday it has chosen Boeing's 747-8 aircraft for a new fleet of Air Force One presidential planes, opting against an airliner made by Airbus.

The current aircraft used by the U.S. president -- with its famous blue-and-white color scheme -- is also a 747, but a much older model that dates back more than two decades.

The White House said Wednesday it was "monitoring closely" events in Greece, where a new hard-left government has vowed to reopen the terms of a massive financial bailout and stated opposition to more sanctions against Russia.

U.S. President Barack Obama rang Prime Minister Alexis Tsipras to congratulate him on his recent election victory, a win that has put Athens on a potential collision course with its European neighbors and with Washington.

A naturalized U.S. citizen was jailed Wednesday for five years for attempting to help Venezuela build a nuclear weapon by passing on secret information, the U.S. Justice Department said.

Scientist Pedro Leonardo Mascheroni, 79, and his wife Marjorie Roxby Mascheroni, 71, had pleaded guilty after they were caught trying to pass on classified information to an FBI agent posing as a Venezuelan government official.

Mitt Romney, considering another presidential run, took swipes at potential 2016 rival Hillary Clinton on Wednesday for "cluelessly" conducting foreign policy, and said Barack Obama's brand of economics is hurting Americans.

The 2012 Republican nominee, who lost to Obama, has returned to the political spotlight this month after telling donors he remains interested in a third shot at the White House.

The fight against Islamic State jihadists is taking place online as well on the battlefield, with 18,000 Twitter accounts linked to the group suspended in recent months, according to a U.S. expert.

IS supporters "are under significant pressure, with the most active and viral users taking the brunt of the suspensions" J. M. Berger, a fellow at the Brookings Institution who tracks militants on social media, told lawmakers on Tuesday.

The U.S. state of Georgia executed a double killer Tuesday whose lawyers said he was intellectually disabled, after last-minute pleas for his life were thrown out.

The Supreme Court turned down the final appeal from lawyers of Warren Hill, 54, who was pronounced dead from lethal injection at 7:55 pm (0055 GMT), a prison spokeswoman said.

Iran has told the United States that Israel should expect consequences for an attack on the Syrian-controlled Golan Heights that killed an Iranian general, a senior official said Tuesday.

Revolutionary Guards General Mohammad Ali Allahdadi died alongside six fighters from Lebanon's Hezbollah group in the January 18 attack on forces supporting President Bashar Assad in Syria's civil war.

The United States delivered on Tuesday a shipment of military vehicles to Lebanon to aid the Lebanese army in its mission to combat terrorist threats, in particular along its eastern border.

The U.S. embassy announced via its account on Twitter that the U.S. “delivered dozens more brand new armored Humvees to protect the Lebanese army soldiers in the line of duty.”