The planned meeting between Russian President Vladimir Putin and U.S. President Barack Obama in New York on Sept. 28 was organised by "mutual agreement" and will focus on Syria, Kremlin spokesman Dmitry Peskov said on Thursday.

Peskov also told a conference call with journalists that the crisis in Ukraine would be discussed "if time allows".

The meeting between the two presidents will take place after Putin's address to the United Nations, Peskov said, adding that the leaders' talks may last between 50 minutes and an hour.