(Adds Rouhani and Revolutionary Guards commander; cut deputy foreign minister)
BEIRUT, July 26 (Reuters) - Iran will reciprocate if the United States imposes new sanctions on it, president Hassan Rouhani said on Wednesday according to state media, casting further doubt over the outlook for the 2015 Iran nuclear accord.
The U.S. House of Representatives voted on Tuesday to slap new sanctions on Iran, Russia and North Korea, although it was unclear how quickly the bill would make its way to the White House for President Donald Trump to sign into law or veto.
State media quoted Rouhani as citing a verse from the Koran saying: "If the enemy puts part of their promises underfoot then we will also put part of it underfoot. And if they put all of their promises underfoot then we will put promises underfoot."
But he added: "The Koran also advises that if enemies are really pursuing peace and want to put enmity aside and act appropriately toward you, then you should do the same."
He said that parliament would take the initial steps in responding to any U.S. moves and that any necessary further steps would also be pursued.
On Tuesday, Trump issued a veiled threat against Iran, warning it to adhere to the terms of the 2015 nuclear deal it signed together with world powers or else face "big, big problems."
A week after certifying Iran as complying with the agreement negotiated by Democratic President Barack Obama, Trump has made it clear that he remains extremely wary of Tehran.
The Iranian side appears equally wary of Washington, with a senior Revolutionary Guards commander issuing a similar threat in return on Wednesday.
"The Trump government, more than before, should be cautious and precise with their military approach in the Islamic revolution environment," Brigadier General Masoud Jazayeri, deputy chief of staff of Iran's armed forces was quoted by the Tasnim news site as saying on Wednesday.
"We will confront any American mischief with a response that will make them sorry," he said.
The head of the Guards was quoted as saying last week that Washington should move its bases and avoid "miscalculations" over new sanctions against Tehran. The United States has bases in Qatar and Kuwait across the Gulf from Iran, while the U.S. Fifth Fleet is based in nearby Bahrain. (Reporting by Babak Dehghanpisheh; Editing by Hugh Lawson)