CBS News - Russia has accused the Trump administration of a "provocation" for its decision to send about 1,000 more U.S. troops to the Middle East amid soaring tension with Iran. Acting U.S. Secretary of Defense Patrick Shanahan announced the troop surge on Monday -- the latest in a tit-for-tat escalation with Iran following attacks on two tankers near the Persian Gulf, which the U.S. has blamed on the Islamic Republic.

U.S. military officials have told CBS News senior national security correspondent David Martin that the additional troops are being deployed to provide greater defense against possible Iranian missile attacks and additional surveillance in the sensitive region.

"The recent Iranian attacks validate the reliable, credible intelligence we have received on hostile behavior by Iranian forces and their proxy groups that threaten United States personnel and interests across the region," Shanahan said on Monday. "The United States does not seek conflict with Iran. The action today is being taken to ensure the safety and welfare of our military personnel working throughout the region and to protect our national interests."

Iran and its backers in Moscow, however, have consistently accused the Trump administration of fanning the flames in the region, starting with the president's decision to unilaterally pull the U.S. out of the international nuclear agreement with Iran and ratcheting up incrementally since then with mounting economic sanctions and blacklisting of Iran's state institutions.

Mounting blame, mounting pressure
The White House has pointed to Iran's support for militia groups from Syria to Yemen as evidence of its regional malign influence, and in recent months to the attacks on merchant vessels around the vital shipping channel of the Strait of Hormuz, as cause for bolstering the American military presence in the region.

Iran denies any role in the tanker attacks, and has voiced frustration at the mounting allegations from Washington that its elite Revolutionary Guard Corp was behind them. On Monday, the Iranian regime said it was going to increasing its production of uranium beyond the constraints of the crumbling nuclear deal it struck with global powers, including the U.S., in 2015.

The Pentagon reacted by releasing high-resolution photos which purportedly show Revolutionary Guard members attempting to destroy evidence of the attack on a Japanese oil tanker last week.

Shortly after the Pentagon released the new photos, Shanahan announced the troop surge. The Trump administration insists it is not seeking war with Iran, but does not hide the fact that plans for military action have been drawn up.

In the meantime the White House continues to try and convince allies Iran was behind the tanker attacks, to mount international support on the Iranians.

"We should not yield to nuclear extortion from the Iranian regime," State Department spokesperson Morgan Ortagus said on Monday, reacting to Iran's threat to ramp up uranium enrichment.

While the U.S. tries to gain international support, CBS News correspondent Charlie D'Agata reports from the United Arab Emirates -- near where the tanker attacks have taken place -- that the White House still has significant convincing to do. Officials in the UAE have been very careful not to directly blame Iran for the attacks, saying instead that the sabotage was the work of an unnamed "state actor."

CBS News contributor Michael Morell, a former deputy director of the CIA, said he's been persuaded by the photographic and timeline evidence put forth by the White House, as well as the fact that Democratic Rep. Adam Schiff -- whom Morell noted is "no fan" of the current administration -- called the evidence that Iran was behind the tanker attacks convincing.

Morell said there was no immediate nuclear threat from Iran, even if it does ramp up uranium enrichment -- the Islamic Republic would still be at least a year away from developing an atomic bomb. Morell said he believed the White House was being "prudent" by demonstrating its resolve to defend its interests in the region, but stressed that "miscalculation could bring us to conflict."

Both of the ships damaged last week have now been towed to the waters off the coast of the UAE port of Fujairah. D'Agata said CBS News was told in no uncertain terms that taking a boat out to try and film the stricken vessels was strictly forbidden, which gives an idea how sensitive the issue is in the region.

Resisting the pressure
The Iranians have insisted the White House's "maximum pressure" campaign won't work, and with Russia's backing, any change in behavior from Tehran seemed unlikely on Tuesday.

"Iran will not wage war against any nation," President Hassan Rouhani said on Iranian state TV on Tuesday, adding: "Despite all of the Americans' efforts in the region and their desire to cut off our ties with all of the world and their desire to keep Iran secluded, they have been unsuccessful."

Deputy Russian Foreign Minister Sergei Ryabkov told Russian news outlets on Tuesday that the U.S. should abandon its plan to send hundreds more troops to the Middle East, calling it a provocation.

Ryabkov said Moscow had warned Washington and its allies repeatedly against what he called an "unthinking and reckless pumping up of tensions in an explosive region."

He accused the Trump administration of "unending and sustained U.S. attempts to crank up political, psychological, economic and yes military pressure on Iran in quite a provocative way. They (U.S. actions) cannot be assessed as anything but a conscious course to provoke war," Ryabkov said according to Russian state media.

Responding to U.S. officials' insistence that war was not the objective, Ryabkov said, "if that's really how it is then the U.S. should step back from reinforcing its military presence."

Russia's U.N. ambassador implicitly accused the United States of destabilizing the region by escalating what he called "aggressive, accusatory rhetoric and artificially fueling anti-Iranian sentiment."

Vassily Nebenzia condemned the attacks against the tankers at a U.N. Security Council meeting Monday, calling for an international investigation to identify the organizers and hold them accountable.

"We underscore that artificially stoking tensions and hasty accusations are hardly conducive to an impartial, international investigation," Nebenzia said without naming the U.S. explicitly. "On the contrary they politicize it and erode trust in such a process."

"Pandora's box"
But both Russia and China, which have deep business ties with Iran, have called on the Islamic Republic not to violate the nuclear deal by ramping up uranium enrichment, but they also place the blame for the soaring tension in the Persian Gulf more on Washington than Tehran.

Chinese State Councillor Wang Yi, the country's senior diplomat, said the U.S. should abandon its policy of putting Iran under "extreme pressure" to resolve the standoff.

Wang told reporters that China was "of course, very concerned" about the situation.

"We call on all sides to remain rational and exercise restraint, and not take any escalatory actions that irritate regional tensions, and not open a Pandora's Box," he said.

"In particular, the U.S. side should alter its extreme pressure methods," Wang told reporters in Beijing. "Any unilateral behaviour has no basis in international law. Not only will it not resolve the problem, it will only create an even greater crisis."