Sen. Marco Rubio (R., Fla.) sent a letter to Attorney General William Barr on Monday asking him to look into whether former secretary of state John Kerry violated the Logan Act or Foreign Agents Registration Act (FARA) with his interactions with Iranian officials in relation to the Iran nuclear deal.

"The American people deserve to know that U.S. laws are enforced regardless of any individual's past position," Rubio states. "The Department of Justice should, therefore, make a determination on whether or not former Secretary of State John F. Kerry's recent actions related to the Joint Comprehensive Plan of Action with Iran potentially violate the Logan Act or the Foreign Agents Registration Act."

Today I urged the DOJ to investigate whether former Secretary of State John F. Kerry’s actions since leaving office related to the #Iran nuclear deal violate the Logan Act or FARA –> https://t.co/yxq4O2bmke pic.twitter.com/V52wxcd5mL — Senator Rubio Press (@SenRubioPress) May 13, 2019

Rubio is renewing the push to have the Justice Department look into potential violations after having requested then-Attorney General Jeff Sessions to examine whether Kerry acted improperly.

In his letter to Barr, Rubio included his previous letter to Sessions, sent in September of 2018, which highlighted Secretary Kerry's admission that he had met with Iranian foreign minister Javad Zarif "probably three or four times," since the end of the Obama administration. The Boston Globe reported last May that Kerry had been "quietly seeking to salvage Iran deal he helped craft" and described Kerry has engaging "in some unusual shadow diplomacy," with Zarif.

The original letter to Sessions cited reporting from the Boston Globe about how Kerry had been working "with a group of officials who were his top advisers at the State Department, and who helped craft and negotiate the Iran deal in the first place," to shape media coverage of the potential termination of the Iranian deal.

According to the Globe, "The group claims to be responsible for 100 news articles, 34 television and radio hits, and 37 opinion pieces on the Iran question. They do fact checks of criticisms of the agreement and blast them out to an e-mail list of nearly 4,000 policymakers and foreign policy experts."

Rubio's letter comes just days after President Donald Trump suggested Kerry should be held accountable for his interactions with Iranian officials.

"John Kerry speaks to them a lot," President Trump said in an exchange with reporters last Thursday. "John Kerry tells them not to call. That's a violation of the Logan Act. And frankly, he should be prosecuted on that."