The United States is said to have informed Israel in advance about Friday's telephone conversation between President Barack Obama and his Iranian counterpart Hassan Rohani.

The first such direct high-level talks between the leaders of the US and Iran since 1979, however, are unlikely to have allayed Israel's fears over Tehran's nuclear programme.

According to an Obama administration official, the Israeli government was informed of the historic talks in advance.

The conversation took place following a seismic shift in tone between Tehran and Washington over Iran's contentious nuclear programme.

The call was made on the sidelines of the UN General Assembly in New York, hours before Rohani left the US. The telephone conversation, which took place at 2:30pm (18:30 GMT), lasted for about 15 minutes.

Although it is still unclear who called whom, reports suggest Rohani took the initiative.

"While there will surely be important obstacles to moving forward and success is by no means guaranteed, I believe we can reach a comprehensive solution. The test will be meaningful, transparent, and verifiable actions, which can also bring relief from the comprehensive international sanctions that are currently in place," said Obama.

Rohani had earlier said that Iran wants to strike a deal with the western powers in three to six months over the nuclear issue.

Prior to the telephone conversation, Rohani told a press conference: "The environment that has been created is quite different from the past, and those who have brought the change were the people of Iran. The first step has been taken here which is a beginning for better relations with other countries and in particular, between the two great nations of Iran and US."

It is also believed that the latest talks between US Secretary of State John Kerry and Iranian Foreign Minister Mohammad Javad Zarif paved the way for the Obama-Rohani conversation.