A senior Iranian official has ruled out the prospect of reviewing and revising the 2015 multilateral nuclear agreement with the P5+1 group of countries, saying Iran will never yield to foreign pressure on the deal, its defense program or regional role.

The Islamic Republic of Iran will never accept any other condition such as the West's insistence on including issues like the country's defense program or its regional role in the nuclear deal, Ali Akbar Velayati, a senior adviser to Leader of the Islamic Revolution Ayatollah Seyyed Ali Khamenei on international affairs, told reporters in Tehran on Monday.

"The JCPOA (the nuclear agreement, officially known as the Joint Comprehensive Plan of Action) is precisely what was signed by Iran and other parties to the JCPOA in writing; neither a word more, nor a word less," Velayati added.

He emphasized that Iran had fulfilled its commitments under the JCPOA despite certain problems.

Iran and the five permanent members of the United Nations Security Council – the United States, France, Britain, Russia and China – plus Germany signed the nuclear agreement on July 14, 2015 and started implementing it on January 16, 2016.

Under the JCPOA, Iran undertook to put limits on its nuclear program in exchange for the removal of nuclear-related sanctions imposed against Tehran.

US President Donald Trump has repeatedly described the JCPOA, which was negotiated under his predecessor, Barack Obama, as “the worst and most one-sided transaction Washington has ever entered into,” a characterization he often used during his presidential campaign when he threatened to tear the deal up.

The American head of state has repeatedly claimed that Iran’s missile program is in violation of the UN Security Council Resolution 2231, which endorses the JCPOA.

Trump said he wanted America's European allies to use the 120-day period before sanctions relief again came up for renewal to agree to tougher measures and new conditions, otherwise Washington would pull out of the deal.

Iranian President Hassan Rouhani said on Saturday that the United States would be making a "big strategic mistake" if it decided to pull out of the landmark agreement on Tehran’s nuclear program.

Rouhani added that the world would see that Washington's withdrawal from the nuclear deal would be the "US’ biggest folly in its political relations with the world and particularly with our region."

The Iranian chief executive also on February 6 said the Islamic Republic would never hold negotiations either about the JCPOA or its defensive missile program.

"We never regard other issues linked to the JCPOA. The JCPOA is a seven-sided agreement…The JCPOA is an international agreement which has been endorsed by the Security Council Resolution 2231," Rouhani said at a press conference in the presence of Iranian and foreign reporters in Tehran.

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Iran will continue its presence in Syria

Elsewhere in his remarks, Velayati rejected Israel's claims that Iran was controlling an air base outside the Syrian city of Palmyra.

"Iran's presence in Syria is aimed at helping Syria's legitimate government and the oppressed people of this country and has no other purposes," Velayati said.

The senior Iranian official emphasized that Iran would continue its presence in Syria but not based on the Israeli regime's claims.

He said Iran was an important country in the Middle East and had the right to answer the calls of other friendly nations in the region or those who are members of the resistance front.

"In case of a call for consultation or any other help which leads to the strengthening of the resistance front, we will give a positive response," Velayati pointed out.

In a statement on Saturday night, the Israeli military forces claimed that Iran for some time has been operating the T-4 Air Base in Syria next to Palmyra, with support from the Syrian military and with permission from the Syrian government.

The statement came on the same day that the Syrian military hit at least one intruding Israeli F-16 warplane that attacked positions inside the Syrian territory, sending it down in flames and smoke.

Syria’s state TV cited a military official as saying that Syrian aerial defense had responded to Israeli “aggression” against an army base in the center of the Arab country.

Later in the day, the Israeli military claimed that it had attacked positions inside the Syrian territory after it intercepted an Iranian drone launched from Syria.

A pro-Syrian military alliance said that the Israeli claim about a drone intrusion was bogus.

Iran also rejected as "ridiculous" claims by the Israeli regime that it had intercepted an Iranian drone launched from Syria, stressing that the Islamic Republic's military advisory presence in the Arab country was at the request of Syria’s "constitutional and legitimate" government.

Iranian Foreign Ministry Spokesman Bahram Qassemi said, "Claims about the flight of an Iranian drone … are too ridiculous to be addressed because the Islamic Republic of Iran has advisory presence in Syria at the request of the country's legitimate and constitutional government."

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