Foreign investors are expected to flood the Iranian market as sanctions relief expands the country's oil potential, officials said Monday.

Iran could see sanctions pressures ease if a framework agreement reached last week in Switzerland enters into force in July. Iran, under the terms of the agreement, would pull back substantially from the brink of developing a nuclear weapon.

Iran is limited to around 1 million barrels of oil per day in exports under the terms of a November 2013 deal with international powers. Exports could double if all sanctions are released later this year.

"After July 1, foreign investors will flock to Iran, particularly to the oil and petrochemical sectors," Abbas Sheri-Moqaddam, director of the National Petroleum Co., said. "We must prepare ourselves for such an event starting now.

Iranian Oil Minister Bijan Zangeneh said during the weekend the Islamic republic could return as a dominant force in the Organization of Petroleum Exporting Countries once the nuclear deal is formalized. Iran holds the third-largest proven oil reserves among OPEC member states, behind Venezuela and Saudi Arabia, respectively.

The National Petroleum Co. director said the domestic oil and petrochemical sector was in dire need of investments to return to its full glory.

"Under the present circumstances, this industry needs $8 billion a year of investment to make up for its backwardness," he said.

The Iranian nuclear agreement faces an uphill battle in a U.S. Congress controlled by leaders wary of Iran's regional influence.