NEW YORK — A veteran tabloid publisher testified Tuesday that he pledged to be Donald Trump’s “eyes and ears” during his 2016 presidential campaign, recounting how he promised the then-candidate that he would help suppress harmful stories and even arranged to purchase the silence of a doorman.

The testimony from David Pecker was designed to bolster the prosecution’s premise of a decades-long friendship between Trump and the former publisher of the National Enquirer that culminated in an agreement to give the candidate’s lawyer a heads-up on negative tips and stories so they could be quashed.