The United States accused Libyan separatists of theft Sunday after they loaded oil onto a North Korean tanker for a second consecutive day, warning would-be buyers of possible liabilities and sanctions.

The separatists are former rebels who have turned against the interim authorities in the restive north African country after toppling veteran dictator Moamer Kadhafi in the 2011 uprising.

The U.S. State Department sought the propaganda edge Wednesday evoking writer Dostoyevsky to denounce what it called Russian President Vladimir Putin's "fiction: 10 false claims about Ukraine."

In a mounting war of words between the former Cold War foes, U.S. and Russian officials have in recent days put out starkly different versions surrounding the deployment of Russian troops in Ukraine's Crimea peninsula.

The United States pressed Iraq Monday to explain media reports that it had signed a contract to buy arms from Iran, a move forbidden under a United Nations embargo.

"We've certainly seen those reports. If true, this would raise serious concerns," State Department spokeswoman Jen Psaki said.

Washington is to demand Israel implement a partial settlement freeze after U.S. Secretary of State John Kerry presents his framework for extending peace talks, army radio reported on Wednesday.

Quoting U.S. negotiators involved in the talks, the radio said the United States was hoping to obtain a freeze on construction in isolated settlements outside the major West Bank blocs, which Israel hopes to retain in any peace deal.

U.S. Vice President Joe Biden urged Ukrainian President Viktor Yanukovych Tuesday to pursue dialogue and compromise to end the country's crisis as he called for the "immediate" pulling back of riot police.

In a phone call, Biden "emphasized that the only viable path to peace and stability in Ukraine is through continued dialogue and genuine compromise to form a new government that can earn the confidence of the Ukrainian people," the White House said in a statement.

The U.S. administration stood by its policy on Syria Monday, denying that Secretary of State John Kerry had called for a change of strategy and the arming of opposition rebels.

As January marked the deadliest month in the conflict with almost 6,000 killed, some U.S. media claimed the top diplomat had said Washington's policy was failing.

Washington reiterated on Saturday the long-standing advice that U.S. citizens avoid all travel to Lebanon in light of recent security incidents in the country.

“U.S. citizens living and working in Lebanon should understand that they accept risks in remaining in Lebanon and should carefully consider those risks. This supersedes the Travel Warning issued on October 9, 2013,” the Department of State said via twitter.

The United States has raised concerns with Moscow over a reported Russian test of a cruise missile and is evaluating whether it breaks a 1987 treaty, a U.S. official said Thursday.

Washington has raised "the possibility of... a violation," State Department spokeswoman Jen Psaki said, amid reports that Russia had tested a new ground-launched cruise missile.

The lawyer representing 20 Salafists given suspended sentences over an attack on the U.S. embassy in Tunis demanded the "truth" Tuesday about the killing of four assailants, hinting that embassy staff were responsible.

Defense lawyer Monaem Turki branded as "political" the appeals trial of the 20 suspects, which comes after Washington sharply criticized the original sentences for being far too lenient.

U.S. Vice President Joe Biden urged Ukrainian President Viktor Yanukovych Monday to pull back riot police and work with the opposition on "immediate measures" to de-escalate tensions between the government and protesters.

In a phone call, Biden -- "underscoring that no time should be lost" -- also warned that "declaring a state of emergency or enacting other harsh security measures would further inflame the situation and close the space for a peaceful resolution," according to a White House statement.