U.S. President Barack Obama Thursday called on the "entire" government in Tehran to seize on nuclear talks with world powers to end Iran's economic isolation.

Obama made a direct effort to build political support among Iranians in favor of the nuclear diplomacy led by the government of President Hassan Rouhani in an annual video message marking Nowruz, new year celebrations.

U.S. President Barack Obama on Tuesday called for a G7 summit next week to discuss the escalating showdown with Russia over Crimea.

The White House said Obama asked fellow leaders of the grouping -- minus G8 member Russia -- to join him in the Hague, where he will be attending a nuclear security summit, to discuss the crisis and how to support Ukraine.

Michelle Obama will look to dispel growing mistrust between the United States and China through a weeklong tour of the Asian power focused deliberately on soft issues, officials said Monday.

Accompanied by her two daughters and mother, the U.S. first lady will head Wednesday on a tour to some of China's most celebrated sites including the Great Wall, the ancient terracotta warrior sculptures of Xian and a panda preserve.

U.S. President Barack Obama on Monday told Palestinian leader Mahmoud Abbas that both he and Israeli leaders must make tough political decisions and take "risks" for peace.

Meeting Obama at the White House, Abbas said Israel's release of a fourth tranche of Palestinian prisoners by March 29 would show how serious Prime Minister Benjamin Netanyahu was about extending peace talks.

Thousands of Palestinians took to the streets of West Bank cities Monday in support of President Mahmud Abbas's visit to Washington for talks with Barack Obama on the peace process with Israel.

Demonstrators waved the Palestinian national flag as well as that of Abbas's Fatah party, chanting "we are with you, president!" as Abbas was to weigh up an anticipated U.S. request to extend the faltering negotiations with Israel.

Top U.S. diplomat John Kerry urged Palestinian President Mahmoud Abbas on Sunday to work hard to narrow huge differences with the Israelis at a "pivotal" time for peace talks.

Palestinian and Israeli leaders have been locked in talks the U.S. secretary of state fought hard to launch in July after a three-year hiatus, but as negotiations have faltered, Israel has kicked up more obstacles to a peace deal that would end decades of conflict.

Russian President Vladimir Putin on Sunday told U.S. President Barack Obama in telephone talks that the referendum on the Ukrainian region of Crimea joining Russia was "completely in line with the norms of international law," the Kremlin said.

Putin also told the U.S. president that any Organization for Security and Cooperation in Europe (OSCE) monitoring mission in Ukraine should cover "all Ukrainian regions" and not just Crimea.

An Israeli minister on Sunday said Washington's top diplomat was "wrong" for pressuring Israel in peace talks, a day before Palestinian leader Mahmoud Abbas visits the White House.

His remarks came two days after U.S. Secretary of State John Kerry criticized Israeli Prime Minister Benjamin Netanyahu's repeated demand that the Palestinians recognize Israel as a Jewish state.

As Palestinian President Mahmud Abbas prepares to touch down in Washington for a meeting on Monday with Barack Obama, an extension of peace talks with Israel looks far from certain.

Palestinian and Israeli leaders have been locked in talks U.S. Secretary of State John Kerry fought hard to launch in July after a three-year hiatus, but as negotiations have faltered, Israel has kicked up more obstacles to a peace deal that would end decades of conflict.

Since his return to the Kremlin, Vladimir Putin has grown more powerful than ever before. The strongman, who has ruled Russia for the past 14 years, has muzzled his opponents, check-mated the West on Syria and is now on the verge of annexing Crimea.

On Friday, the Kremlin upped the ante further, hinting it could move forces beyond Ukraine's peninsula to protect his compatriots.