FILE: House Minority Whip Steny Hoyer (D-Md.)  (AP Photo/J. Scott Applewhite)

House Minority Whip Steny Hoyer (D-Md.) said Thursday he does not support efforts to legalize marijuana in Maryland, saying it is a “threshold drug” and leads to the use of more harmful substances.

“I’m not a proponent of legalization of marijuana,” Hoyer said during an interview on C-SPAN’s "Newsmakers."

Hoyer said he was initially amenable to the idea of legalization decades ago when former Baltimore Mayor Kurt Schmoke began advocating for drug decriminalization. But Hoyer said as he learned of the drug’s harmful consequences, he changed his mind.

"As I talked to people who deal with drug abuse issues, with rehabilitation issues, I became convinced that marijuana was, in fact, a threshold drug and it would lead to the use of harder, very harmful drugs,” he said.

Hoyer’s remarks come the day after Maryland Gov. Martin O’Malley (D) expressed his opposition to the idea during the annual “Annapolis Summit” radio show broadcast on the opening day of the state’s legislative session.

“I’m not much in favor of it,” O’Malley said.

Bills to legalize marijuana are expected to be introduced in both chambers of the Maryland General Assembly.

National polls have shown increasing public support for legalization. Colorado began selling marijuana legally on Jan. 1.