U.S. President Barack Obama reacts while talking about Newtown and other mass killings during an event held to announce new gun control measures at the White House in Washington January 5, 2016. REUTERS/Kevin Lamarque

WASHINGTON (Reuters) - President Barack Obama said on Thursday that he will not campaign for Democrats who don’t back gun reforms, part of his effort to make tougher gun laws a cause in the November 2016 presidential and congressional elections.

“I will not campaign for, vote for or support any candidate, even in my own party, who does not support common-sense gun reform,” Obama wrote in an op-ed column in the New York Times.

“All of us need to demand leaders brave enough to stand up to the gun lobby’s lies,” Obama wrote. “All of us need to demand that governors, mayors and our representatives in Congress do their part.”