Nathalie Tocci's comments came amid escalating tension between the U.S. and Iran over attacks on foreign oil tankers in the Gulf of Oman. | Carlos Barria/AFP via Getty Images) Top EU adviser blames US for Iran tensions Oil tanker attacks are ‘not a particularly extreme or radical response’ to what Tehran views as American escalation in the Gulf, Nathalie Tocci says.

A special adviser to EU foreign policy chief Federica Mogherini blamed the United States on Tuesday for a rise in tensions between Iran and the West.

"This is happening for one reason that has not been cited so far, which is the fact that the United States has violated the Joint Comprehensive Plan of Action, meaning the Iran deal," Nathalie Tocci said on BBC radio's Today program, telling the U.S.: "You're not living up to your side of the bargain."

Tocci's comments came amid escalating tension between the U.S. and Iran over attacks on foreign oil tankers in the Gulf of Oman. The United States blames Tehran, which denies it was responsible. They also came just hours before Mogherini is due to hold talks with U.S. Secretary of State Mike Pompeo in Washington.

The EU has shied away from endorsing U.S assertions that Iran was definitely responsible for the attacks on the tankers. But Tocci said it is reasonable to assume it had carried out the attacks.

"We still don't have actually verifiable proof as to exactly what happened and who did what," she said, before adding: "I think it is reasonable to expect that Iran, although it is denying it, has indeed done it."

Tocci continued: "I think it is a response, and not a particularly extreme or radical response, but it definitely is a response, to what it [Tehran] views as being a U.S. escalation in the Gulf. And this is a very dangerous situation, because obviously escalation leads to retaliation."

Asked whether America's decision to unilaterally withdraw from the 2015 Iran nuclear deal justifies Iran's alleged sabotage of the tankers, Tocci said: "Well, I think if there is an escalation on one side, and there has been an escalation on one side meaning on the side of the United States, it is all only reasonable, very unfortunately, and obviously I'm not trying to sort of justify and condone it ... it is only reasonable to expect that there is going to be retaliation on the other side."

Tocci told the BBC that while neither the U.S. nor Iran "really wants a war ... there could be an accidental war that is being triggered by this cycle of escalation and retaliation."

The Pentagon announced Monday it is dispatching an additional 1,000 troops to the Middle East in response to the oil tanker attacks. The move came after Iran said Monday that it would within 10 days exceed the 300 kilograms of low-enriched uranium it is allowed to keep under the nuclear deal.

Asked whether Europe should send troops to the Middle East if the U.S. requested it, Tocci said: "No."

"I think that Europe's role really should be that of trying to attempt to sort of reverse this vicious cycle, and therefore no I don't think this is what we should be doing," Tocci said. "I think what we should be doing is trying to make sure that Iran itself sees an interest in actually living up to its side of the bargain although the United States has violated it. And the only way in which we can do that is actually to double our efforts to ensure that we live up to our end of the bargain of the nuclear deal."

Separately, in an interview with the Kremlin-backed Russia Today network published Monday, Tocci said: "If I were Iran I would probably not stick with the JCPOA because indeed, as I said, the social contract can only hold if both sides live up to the bargain."