This one-day trip is also seen as evidence of the balancing act that France and other European nations find themselves in, following Donald Trump's promise to withdraw the U.S. from the 2015 Iranian nuclear deal if major flaws aren't fixed.
"In the current situation, as the hegemonic regimes are making threats against the Islamic Republic of Iran or conducting war crimes in the region, the task of the armed forces is to enhance defence capabilities in all fields, including missile systems".
Yadollah Javani, the Supreme Leader's adviser at the Islamic Revolutionary Guard Corps (IRGC), also said it would be a "miscalculation" for the West to think Iran is willing to negotiate on its missile programme.
Iran's ballistic missile capacity and position "worries us enormously", Le Drian said last week at a news conference with Russian Foreign Minister Sergey Lavrov.
The diplomat said he would raise the matter during his planned meetings with Foreign Minister Mohammad Javad Zarif and other senior Iranian officials in Tehran.
"The country's defense capabilities will continue non-stop and foreigners do not have the right to enter this field", Jazayeri said Monday, according to the semi-official Fars news agency.
In a separate statement, Le Drian called upon the worldwide community to take action to prevent Iranian missiles from becoming a threat to "all regional actors".
The French Foreign Ministry even issued a statement ahead of the trip, which said Le Drian would pursue "a frank and demanding dialogue with Iran". Trump's obduracy in killing the #JCPOA stems from the same unsafe imprudence.
France is a signatory of the Joint Comprehensive Plan of Action (JCPOA), the 2015 deal which put limitations on Iran's nuclear energy program in exchange for lifting worldwide sanctions.
Abolghassem Delfi, Iran's ambassador to France, has said that Tehran and Paris ties have been on a positive trend since the conclusion of the 2015 nuclear deal.
According to reports, some of the changes to the deal that Trump has demanded include the opening of Iranian military bases to worldwide inspectors, and the curbing of Iran's missile programme - both of which are not covered by the current agreement, and are vigorously opposed by Iran.
Since the lifting of the sanctions in January 2016, French automakers have piled into Iran's resurgent market, helping turn around a period of slipping sales, which occurred when they left the country in 2012.
Iran insists its ballistic missile program is for purely defensive purposes, and has denied accusations by the U.S., France and the United Nations of supplying missile technology to Houthi rebels in Yemen, who have fired ballistic missiles into Saudi Arabia.