Two administration officials, speaking on condition of anonymity, outlined the campaign in a teleconference with reporters, stressing efforts were being made at the United Nations and with partners in the region to condemn and isolate the regime. - AFP (File Photo)

WASHINGTON: The United States is studying whether war crimes charges can be brought against Syria to pressure its regime to end a bloody crackdown on dissent, a senior administration official said Friday.

The official said other measures, including sanctions targeting the country's oil and gas sector, were being considered as part of a broader diplomatic campaign to increase pressure on Syria's President Bashar Assad.

Two administration officials, speaking on condition of anonymity, outlined the campaign in a teleconference with reporters, stressing efforts were being made at the United Nations and with partners in the region to condemn and isolate the regime.

“Other things we are looking into is whether there are ground for charges related to war crimes, whether referrals on that are appropriate,” said one official.

“And we're also looking at additional economic steps, and one in particular has to do with the oil and gas sector in Syria.”

Syria has responded to spreading protests against Assad's rule by intensifying a crackdown, deploying its military to assault towns along the northern border with Turkey, which has set off a wave of refugees across the border.

More than 1,200 people have died and some 10,000 have been detained in Syria since the mid-March eruption of pro-democracy protests inspired by the uprisings that toppled long-standing rulers in Egypt and Tunisia.

President Barack Obama has called on Assad to either lead a transition to democratic rule or “get out of the way.” But he has come under fire from some in Congress for not taking a tougher stance, with critics pointing out that he has not called on Assad to step down as he did in the case of Libyan leader Moamer Qadhafi.

The State Department acknowledged on Thursday that Assad appeared to be responding to calls for political change “in the negative.”

State Department spokeswoman Victoria Nuland said the United States was stepping up contacts inside and outside Syria with “brave Syrians who stand for change.”

The administration officials said US ambassador to Syria Robert Ford was in touch with members of the opposition and closely following the situation on the ground.

“We're in touch with Arab League officials, with bilateral partners in the region, as well as with the Turks in order to build on the pressure for Bashar to lead, or basically get out of the way at this point,” said one of the officials.

Meanwhile, according to the officials, there were signs of increased organization among the opposition, including coordinated nighttime protests.

The officials said the regime had taken some steps to reach out to the Syrian opposition, but had not done enough and had moved too slowly to outpace the growth and spread of protests.

For instance, the announcement Thursday that a hated billionaire in Assad's inner circle, Rami Makhluf, was devoting part of his fortune to charity was “almost ludicrous at this point,” one of the officials said.

“It's not close to enough,” he added.