Cameron Kasky has called out US President Donald Trump following his speech to the National Rifle Association, saying he is a "professional liar".
Kasky was one of the students who survived the mass shooting at Marjory Stoneman Douglas High School in Parkland, Florida on Valentine's Day.
Mr Trump had spoken at an NRA meeting for the third year in a row, defending the second amendment, which allows Americans to have guns, and called the NRA a "great organisation".
"He's a professional liar who will say anything to appease whatever crowd he's at," Kasky said. "If he's in front of families he might say something in support of commonsense gun reform, but then when he's at the NRA he'll say something to get a big cheer."
In the wake of the Parkland shooting, which killed 17 people, Mr Trump said he would take on the NRA, including introducing measures to raise the age limit for buying rifles.
But since then, no major new federal gun controls have been imposed, although the administration is pursuing a proposed regulatory ban on "bump stocks," which enable a semiautomatic rifle to fire a steady stream of bullets.
Kasky has been one of the most vocal Parkland students in the wake of the shooting, helping to organise the March for our Lives.
Kasky said the Trump Administration's view on guns was nonsensical and hypocritical, especially given NRA members were ordered not to bring their weapons to the Trump speech.
"You'd think that if someone supported the NRA, they'd want as many 'good guys with guns' in the room as possible, right?" Kasky said. "The hypocrisy is so blatant here and they're just embracing it at this point."