U.S. President Barack Obama joined with the leaders of Australia and the Netherlands on Thursday to demand full access to the crash site of flight MH17.

Speaking in telephone calls with Australia Prime Minister Tony Abbott and Dutch counterpart Mark Rutte, the leaders agreed to work for a full investigation into the shooting down of the Malaysia Airlines jet last week.

U.S. Republican lawmakers on Wednesday called for greater say in any deal reached between the West and Iran over the Islamic republic's controversial nuclear program.

Turkish Prime Minister Recep Tayyip Erdogan said he has stopped talking to U.S. President Barack Obama on the phone, amid growing strains between Ankara and Washington over Syria and the Gaza conflict.

Turkey, a fierce opponent of Syrian President Bashar Assad and an open supporter of armed rebel fighters, felt betrayed when the United States backed away from military action against Damascus in September.

U.S. President Barack Obama voiced outrage Monday that the probe into the downing of a Malaysian airliner was being hampered by Ukrainian rebels and demanded Russian leader Vladimir Putin force them to cooperate.

"The Russian-backed separatists continue to block the investigation. They've repeatedly prevented international investigators from gaining full access to the wreckage. As investigators approached they fired weapons into the air... All of which begs the question what exactly are they trying to hide?" Obama asked angrily in a statement on the White House south lawn.

U.S. President Barack Obama telephoned Israeli Prime Minister Benjamin Netanyahu on Friday to voice concerns about the crisis in Gaza amid an Israeli ground offensive.

Obama said that while the U.S. supports Israel's right to defend itself, "the United States and our friends and allies are deeply concerned about the risks of further escalation and the loss of more innocent life."

The United States said Thursday that Russia's support for separatists in Ukraine created the conditions in which a Malaysian airliner was apparently shot down with the loss of nearly 300 people.

President Barack Obama and Russian President Vladimir Putin spoke by phone on Thursday about tough new sanctions imposed on Moscow on Ukraine.

White House spokesman Josh Earnest did not divulge other topics of the conversation. The Kremlin however said that the two leaders discussed the reported crash of a Malaysian airliner in eastern Ukraine.

President Barack Obama has a simple message for critics who charge that cascading global crises have left his foreign policy flatfooted and U.S. power enfeebled.

Keep calm -- I can handle this.

President Barack Obama Tuesday spoke to Chancellor Angela Merkel for the first time since a row over U.S. spying prompted Germany to turf out the CIA station chief in Berlin.

The White House gave away little of the conversation about the latest espionage scandal to rock the crucial relationship between the U.S. president and Europe's most powerful leader.

U.S. President Barack Obama told his Chinese counterpart Xi Jinping on Monday he was determined to constructively manage growing differences between their two nations, at a time of high tensions in the Pacific region.

In a telephone call, Obama and Xi also discussed the international effort to reach a deal on Iran's nuclear program in Vienna and the need to ensure North Korea complies with demands for it to dismantle its nuclear program, the White House said in a statement.