Although Secretary of State Rex Tillerson took the unusual step of making a press statement in order to refute a negative report about him, and the White House says the president has confidence in him, Tillerson's tenure has been stormy in recent months. And while he didn't exactly knock down a report which said he had called the president a "moron," he faces other problems, among them, tensions with U.N. Ambassador Nikki Haley.

There have been periods of heightened tension between Tillerson and members of the Trump administration, including National Security Adviser H.R. McMaster. In July, the two argued over certifying the Iran nuclear deal for a second time, CBS News reports.

Tillerson also felt certain foreign policy portfolios were being taken from him, besides the Middle East peace initiative being run by Trump son-in-law Jared Kushner. And soon after the president said he didn't intend to certify the Iran deal the next time it came up, Tillerson confronted the reality that the president had effectively outsourced Venezuela policy to Sen. Marco Rubio, leaving Tillerson on the outside of the policymaking, including decisions about sanctions. One source told CBS News that he "blew up" at the White House for leaving him out.

Officials have told CBS News that Tillerson would not survive another argument like the one over Iran, which is one reason he is tryng to work with Congress to find a way to stop requiring the president to sign off on the deal every 90-120 days and to convince them not to quickly impose sanctions on Iran while he tries to fix the issues the president has highlighted. Diplomats acknowledge that behind closed doors, it is apparent that the secretary of State understands the kind of international fallout that the president's unwavering opposition to the deal would cause. Defense Secretary Mattis and Tillerson continue to have a close alliance, which Tillerson acknowledged Wednesday when he said he talks with Mattis nearly every day. On Tuesday Mattis had said it was in the U.S. national security interest to stay in the deal.

Another source of tension was a remark Tillerson made about the president's comments on the racially-motivated violence in Charlottesville, when Mr. Trump indicated that he viewed the actions of counter-protesters as being on par with those of white supremacists. There was "hatred, bigotry and violence on many sides," Mr. Trump said afterwards. Then, on "Fox News Sunday," Tillerson was asked by host Chris Wallace about defending American values to foreign leaders, as they questioned the president's values. "The president speaks for himself," Tillerson said.

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Mr. Trump viewed the recording a few times, and his frustration abated a bit, Tillerson privately divulged to others in his circle.

If there is anyone with whom Tillerson is experiencing tension, it's U.S. ambassador to the U.N. Nikki Haley. Officials complain privately that she has inserted herself into portfolios that are Tillerson's and has not consulted with the State Department before publicly delivering policy views. This is causing confusion among allies, revealing splits within the Cabinet and undercutting the secretary of State. At a speech at AEI, a conservative think tank in Washington, Haley laid out her own view of how to decertify the Iran deal without walking away from it. Tillerson's State Department was not consulted beforehand.

Then last month, Haley invited herself to the meeting with Iran and the foreign ministers of other participant countries in the nuclear deal. This surprised other countries, whose representatives privately told CBS News that this appeared to be an attempt to either undercut the secretary of State or signal distrust of him, a charge Haley's staff denied. Tillerson stuck to protocol and kept his deputy beside him, leaving Haley relegated to the seat behind him.