TEHRAN, April 12 (Xinhua) -- Negotiations between delegations from Iran and the United States will be extended for another day at Pakistan's proposal and at the two sides' consent, the semi-official Tasnim news agency reported early Sunday.

The report said given the "illogical and excessive demands" of the United States and the Iranian delegation's insistence on ensuring national interests, Pakistan proposed to hold another round of negotiations on Sunday and the two sides agreed.

This occurred at the end of the latest round of Pakistani-mediated talks that ended early Sunday in Islamabad, and after the two delegations exchanged texts, according to Tasnim.

The negotiations started at 1 p.m. local time (0800 GMT) on Saturday and continued for more than 14 hours, the report said.

Tasnim said earlier that certain serious differences still remain between the two sides, adding that "the ball is now in the U.S. court to put aside its usual excessive demands and replace its ambitious approach with a realistic one."

It quoted an informed source as saying that despite the initial progress achieved in the negotiations between the two sides' expert teams, the delegations still have "serious" differences over the Strait of Hormuz and a number of other issues, and no tangible change has occurred in the talks due to the U.S. "excessive demands."

The report stressed that some Western media are exaggerating the talks' "positive atmosphere" to control global energy prices.

Regarding the latest round, Tasnim said: "Given the U.S. excessive demands, this round appears to be the last chance given by the Iranian team to the Americans to achieve a joint framework."

Delegations from Iran and the United States are in Islamabad for talks aimed at easing tensions in the Middle East following a ceasefire reached earlier this week after more than a month of fighting.