Sources close to the nuclear negotiations between Iran and the so-called P5+1 group of countries say the United States is now pushing for the talks to continue beyond the November 24 deadline. US Secretary of State John Kerry has told his Iranian counterpart Mohammad Javad Zarif that the time has come for the two sides to consider extending nuclear talks, according to the sources. Washington's offer of post-deadline talks, published by US media, is said to have been made in bilateral talks between the top Iranian and American diplomats. According to Press TV, major differences still remain as both sides step up their diplomatic efforts to reach a comprehensive agreement by the end of Monday, which is the deadline for the talks. Reports say Russian President Vladimir Putin and Iranian President Hassan Rouhani are set to discuss the talks in a telephone conversation later on Monday. Iran, the United States, Russia, China, Germany, France and Britain are discussing a final deal that aims to give assurances that Tehran’s nuclear program is exclusively peaceful and, at the same time, lift all sanctions imposed against the Iranian nation over the country’s nuclear energy program. Iran has repeatedly said its nuclear program is for peaceful purposes, including generating electricity and making radio-isotopes for its one million cancer patients.