TEHRAN, September 19. /TASS/. Iran is ready to return to a diplomatic settlement of the conflict with the United States if Washington demonstrates its serious intentions, a senior Iranian source told TASS.

"The ball is on the US side. It is better to return to diplomacy, but we must see a real desire of the United States to return to peace. Whatever document they would like to sign, they must demonstrate that they respect the signatures of both parties. The United States must convince the mediators and Iran of its sincerity," the source said.

The source added that Tehran still considers negotiations on nuclear issues possible, but only after full implementation of the Islamabad agreement, which implied the unfreezing of assets and lifting of oil exports restrictions.

Earlier, the secretary of the Supreme National Security Council of Iran Mohsen Rezaei said that Iran had conveyed to the United States the conditions for ending the war and were awaiting a response from President Donald Trump.