President Obama is clearly worried about keeping the pressure on Democrats over the Iran deal during the August recess, expressing deep concerns to a group of supporters Thursday night that Democratic lawmakers are getting "squishy" in the face of a "fierce" lobbying campaign against the accord.

On a conference call with Obama loyalists Thursday night, the president put the August recess fight in dire terms.

"The stakes could not be higher ... as big as the bully pulpit I have, it's not enough" when it comes to making the case for the Iran deal, he told supporters, according to a recording of the phone call obtained by the Washington Examiner.

Comparing opponents of the Iran deal as the same "array of forces that got us into the Iraq war," he said a "bunch of billionaires who happily finance super PACs" are "putting the squeeze on members of Congress."

"The lobbying that is taking place on the other side is fierce, it is well-financed, it is relentless," he said. "And in the absence of your voices, you are going to see the same array of forces that got us into the Iraq war, leading to a situation in which we forgo a historic opportunity and we are back on the path of a potential military conflict."

"I want everyone on the phone to get moving — do not wait," he told supporters representing liberal activist groups closely aligned with the White House, including Americans United for Change, Move.org and Obama for America.

"Right now the opponents of this deal have been flooding members of Congress and they're feeling it," Obama said.

Obama said he's been meeting with lawmakers, who he argued "don't really buy the arguments" against the deal.

"But I can feel when they start getting squishy ... and you can counteract that," he said.

He concluded the more than 20-minute conference call by thanking supporters for putting up with his long commentary.

"It's pretty rare where something of such consequence is so clearly in front of us ... and you guys have the chance to make history by influencing this whole process," he said. "Don't just sit back and wait, and after the fact, suddenly complain."