According to the White House, the main reason for the call was to discuss Putin’s “June 20 meeting with President Ilham Aliyev of Azerbaijan and Serzh Sargsian of Armenia regarding the settlement of the Nagorno-Karabakh conflict”.

A statement by the Kremlin quoted by Russian media said the call was initiated by Putin to inform Obama about the results of the talks on Karabakh as the U.S. is co-chair of the Minsk group under the Organization for Security and Cooperation in Europe but no detail were given out in both statements.

“President Obama expressed his readiness to intensify efforts together with Russia and with France, as co-Chairs of the Organization for Security and Cooperation in Europe Minsk Group, to achieve a comprehensive settlement to the conflict,” according to the White House.

The two leaders also discussed the Syrian civil war during the call, the White House said.

Obama expressed his concerns to Putin about the failure of the Syrian regime to comply with a cessation of hostilities truce in the country brokered by the UN earlier this year and extended by a U.S. and Russian agreement in April.

“President Obama stressed the importance of Russia pressing the Syrian regime for a lasting halt to offensive attacks against civilians and parties to the cessation,” the White House said.

A readout from the Kremlin quoted by Russian media said Putin asked Obama to encourage moderate Syrian opposition groups to disengage from the al-Qaeda-linked Nusra Front and noted the two leaders’ commitment to "build up coordination of Russian and U.S. actions in Syria in the military sphere."

The White House readout didn't mention military coordination but said "the presidents confirmed their commitment to defeating ISIL and the Nusrah Front."

Discussing conflicts in Eastern Ukraine, Obama urged Putin “to take steps to end the significant uptick in fighting in eastern Ukraine.”

Anadolu Agency