Republicans cut Barack Obama’s most forceful comments on climate change – his mockery of climate denial – from the party’s official live stream of his State of the Union address.



A purported Republican fact-check of Obama’s address, prepared by staffers for the House speaker, John Boehner, clumsily cuts the president off mid-sentence just as he was about to wreck the Republicans’ new default line for talking about climate change: “I am not a scientist.”



The Republican party leadership has adopted wholesale the “I am not a scientist” line over the last few months – casting doubt about climate change while avoiding outright denial. Boehner resorted to the line as recently as last week when asked directly about his position on climate change.



In the full version of the speech, as seen by millions in America and around the world, Obama said: “ I’ve heard some folks try to dodge the evidence by saying they’re not scientists; that we don’t have enough information to act. Well, I’m not a scientist, either. But you know what – I know a lot of really good scientists at Nasa, and Noaa, and at our major universities.”



Those words however did not make the cut in the official House Republican version, billed as an “enhanced webcast” that would be “holding President Obama accountable in real-time”.



The Republican version also avoided the subsequent lines in which Obama said: “The Pentagon says that climate change poses immediate risks to our national security. We should act like it.” There is no reference to the Pentagon in the Republican version.



The cut to the “I am not a scientist line” – which abruptly hits Obama off mid-sentence – was first spotted by commenters on Reddit following the speech.



There was no immediate response from Boehner’s office. However, the outgoing White House adviser, John Podesta, accused Boehner of trying to re-write the record. “Climate deniers are already on the wrong side of history, are now trying to airbrush it,” Podesta tweeted.