The U.S. embassy in Libya has called for oil production in the country to resume, after forces of rebel leader Khalifa Haftar shut down several major oil fields and pipelines.

Haftar's army halted most oil output ahead of Sunday's international peace conference on Libya in Berlin. Libya's National Oil Corporation said the halt will cost the country an estimated $55 million per day.

The U.S. embassy said Tuesday it is "deeply concerned" the shutdown will worsen Libya's humanitarian emergency.

Oil prices fell Tuesday despite the loss of Libyan production.

Haftar's forces are pushing toward the Libyan capital, Tripoli, home of the U.N.-backed international government.

World Leaders Agree to Stop Sending Military Support to Warring Parties in Libya World leaders have agreed to provide no further military support to warring parties in Libya and to sanction those who violate the arms embargo. But there was no commitment to withdraw existing military support. U.S. Secretary of State Mike Pompeo represented the U.S. at the summit Germany's capital Berlin on Sunday to take part in another effort towards peace in a divided country, where General Khalifa Haftar challenges the United Nations-backed government in Tripoli. VOA's Zlatica Hoke reports

Representatives of the two sides did not hold direct talks at the summit in Berlin. Other participants agreed to support a cease-fire and uphold a previously existing U.N. arms embargo in Libya.

However, Turkey has sent soldiers to support the Tripoli government, while Haftar has the backing of Russian mercenaries.