US Secretary of State Marco Rubio reassured Gulf allies on Wednesday that his country “won't do anything” to undermine their security amid negotiations with Iran over a permanent peace deal.Mr Rubio was speaking in Kuwait after visiting the UAE, where he met President Sheikh Mohamed, and before a meeting with Gulf foreign ministers in Bahrain on Thursday.“We're going to be completely aligned with our partners on the Gulf. That's why we're meeting with all of them tomorrow,” he told reporters.“That's why I've taken this trip now. And it's the reason why I'm here. Apart from thanking them for the incredible support they gave us throughout this process, we want them to know and we want to reiterate and begin to talk to them and engage them in conversations about every decision that's made with regards to this negotiation,” he said.“We're not going to do anything that undermines the security of our allies, our long-standing allies in the region,” Mr Rubio said. “So I think that that's something that our partners believe when we say, because we're doing it and we're going to continue to do it. And we're doing it with them now.”The US Secretary of State's visit came after a memorandum of understanding was reached between Iran and the US. The deal ended almost four months of conflict in the region but did not address thorny issues such as Iran's ballistic missile programme and its support for militias in the Middle East.In Kuwait, Mr Rubio said his country does not support tolls or fees in the Strait of Hormuz and that he will convey this message to Gulf officials.“I think the whole world will be against any mechanism that charges money to use an international waterway. It's that simple. The president already said it. That's not going to happen. When we mean open the strait, we mean open the strait, free. So we'll express that tomorrow,” he clarified.“I am certain that not only will every country in the Gulf region be supportive, probably with the exception of Iran, but all the GCC members will be supportive and the whole world will be supportive,” added Mr Rubio.“I know of no country on the planet that supports tolling or a fee for the use of the straits. That's just not, that's not going to happen. The president has been abundantly clear.”Sheikh Meshal, Emir of Kuwait, receives US Secretary of State Marco Rubio at Bayan Palace. AFPInfoMr Rubio said that during his talks in the UAE and Kuwait, he didn’t “sense any doubts about our security assurances because they're real. They're not promises. They're actual. They exist”.He called ties with Gulf partners “long-standing relationships” and added that US and Gulf officials “speak very frankly, very openly, very honestly. We get their input. And that's what we're here to do, to get their input. They are partners.“I'm not here to tell them. I'm here to hear as well. And so I thought that we're very frank and honest. I think we're very strongly aligned.”He also warned that President Donald Trump could reverse the decision to lift some sanctions on Iran if Tehran does not honour its commitments.“Anytime you enter into a negotiation, it's a process of give and take. This is a temporary measure. It's for 60 days. And as a result, we expect them to live up to the commitments they made in Switzerland,” he told reporters.“If they don't live up to those commitments, the president has a lot of options at his disposal, including … reversing these sanctions.” Asked if he believed the Iranians were unified in their negotiation strategy, he said “it doesn't matter”, adding that “what matters is what they do or they don't do”.“They either do the things they claim and agreed to do or they don't. And if they do it, then great. We'll keep moving forward. And if they don't, the president's been clear about what's going to happen and what could happen. But let's hope they do. Let's hope they mean it.”