Bahram Qasemi, the ministry spokesman, told IRNA on Thursday that the reports on Cairo's move were not confirmed officially yet, but if the news is true, Tehran would welcome it.
"Egypt is an important and powerful country both in the Arab and in the Muslim world that can play a key role in creating peace, stability and security in the West Asia region," said Qasemi. "In case the news is confirmed, we will welcome that."
Reuters News Agency reported earlier on Thursday that Egypt conveyed its decision to the United States and other participants in the proposed Middle East Security Alliance (MESA), citing an unidentified source.
Egypt withdrew because it doubted the seriousness of the initiative, had yet to see a formal blueprint laying it out, and because of the danger that the plan would increase tensions with Iran, said an Arab source who, like three other sources quoted in the Reuters story, spoke on condition of anonymity.
Uncertainty about whether US President Donald Trump will win a second term next year and whether a successor may ditch the initiative also contributed to the Egyptian decision, the Arab source said.
"It's not moving well," a Saudi source said of the initiative.
According to IRNA, Qasemi expressed doubt that the proposed initiative could be successful, arguing that NATO was founded in the Western world "under certain historical and geographical conditions, based on a series of certain values and necessities and even very certain commonalities" which were not likely to be copied in the Arab world.
The initiative, which Saudi Arabia first proposed in 2017, also is aimed at limiting the growing regional influence of Russia and China, according to a classified White House document reviewed by Reuters last year.
In addition to the US and Saudi Arabia, the MESA proposed participants include the United Arab Emirates, Kuwait, Bahrain, Qatar, Oman and Jordan.
Two sources said the countries remaining in MESA were moving forward with the initiative and would press Egypt diplomatically to revoke its withdrawal, with one saying that the decision did not appear to be final.
"We all want them back," said the other source. The Arab source, however, said Cairo could not be convinced to return.