Obama: US will consider more steps to stop Russia

Ukrainian army forces patrol in the Tonenkoe town near Donetsk International Airport
Viktor Koshkin | Anadolu Agency | Getty Images
Ukrainian army forces patrol in the Tonenkoe town near Donetsk International Airport

U.S. President Barack Obama said on Sunday that Russian support was behind the latest ceasefire breakdown in Ukraine and said the United States would consider all additional options short of military action to rein-in Moscow over its neighbor.

Read MoreWar is exploding anew in Ukraine

"We are deeply concerned about the latest break in the ceasefire with Russia," Obama told a news conference in New Delhi, adding that "it would not be effective to engage in a military conflict with Russia".

Obama defends Yemen strategy

Obama also defended his administration's drone-based counterterrorism strategy against al Qaeda militants in Yemen, saying the alternative would be to deploy U.S. troops, which he said was not sustainable.

"It is not neat and it is not simple, but it is the best option that we have," Obama told reporters at a news conference.

The United States has not suspended its counterterrorism operations in Yemen after Iran-backed Houthi rebels took over last week, Obama said.

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