The United States has expelled Venezuela's charge d'affaires in Washington and two other diplomats in reprisal for the expulsion of three American diplomats from Caracas, both countries said late Tuesday.

The tit-for-tat move came a day after the expulsion of the Americans, accused of plotting acts of sabotage against the government, the Foreign Ministry in Caracas said.

The U.S. government shutdown had no drastic effect on the military Tuesday but if it remains in place everything from ship repairs to combat training will be disrupted, officials say.

With about half the Pentagon's 800,000 civilian employees placed on unpaid leave, defense officials said the military will soon face a headache trying to make do with less civilian manpower under the shutdown.

U.S. President Barack Obama on Tuesday slammed Republicans for shutting down the government as part of an "ideological crusade" designed to kill his signature health care law.

"I urge House Republicans to reopen the government," Obama said at the White House, as he highlighted a major portion of the health reform program which came into force on Tuesday.

Iranian Foreign Minister Mohammad Javad Zarif accused Israeli Prime Minister Benjamin Netanyahu of lying in his rejection of Tehran's overtures to the West as a cosmetic "charm offensive".

"We have seen nothing from Netanyahu but lies and actions to deceive and scare, and international public opinion will not let these lies go unanswered," Zarif said in an interview with Iranian television broadcast on Tuesday.

U.S. President Barack Obama told U.S. troops in a video message early Tuesday that they would still get paid on time, despite a government shutdown.

Obama earlier signed emergency legislation ensuring that wages would continue for service members, despite much of the government shutting down after Congress failed to defuse a huge federal funding row.

Hopes for a breakthrough in the 30-year estrangement between the U.S. and Iran had an impact on President Michel Suleiman's Gulf tour that was gradually postponed, local newspapers reported on Tuesday.

According to As Safir newspaper, Saudi Arabia postponed Suleiman's visit to Riyadh over the international and regional developments.

U.S. President Barack Obama said Monday he was not giving up hope for a deal to avert a shutdown of the federal government in a matter of hours.

"I am not at all resigned" to a shutdown, Obama told reporters when asked about it.

U.S. President Barack Obama thanked Israeli Prime Minister Benjamin Netanyahu Monday for his "courage" in "good faith" negotiations with the Palestinians on final status issues.

"I commended him for entering into good faith negotiations with the Palestinian Authority. I appreciate the prime minister's courage in being willing to step forward."

President Barack Obama promised Benjamin Netanyahu Monday he would enter talks with Iran with clear eyes and demand verifiable actions, following the Israeli leader's warnings about "sweet talk" from Tehran.

Netanyahu and Obama held talks at the White House, days after Obama's historic call with Iranian President Hassan Rouhani spurred hopes for a breakthrough in the 30-year estrangement between Washington and the Islamic Republic.

Iran's Revolutionary Guards chief said Monday President Hassan Rouhani should have refused a telephone call from his U.S. counterpart, in the first public criticism of the move by a senior official.

Rouhani's landmark conversation with Barack Obama last week was the first contact between leaders of the two countries since the rupture of diplomatic relations in the aftermath of the 1979 Islamic revolution.