Washington (CNN)Two top Republicans working with President-elect Donald Trump's transition team told reporters in a phone call Wednesday evening that they're taking steps toward one of Trump's campaign promises -- to "drain the swamp" in Washington.

Trump communications director Jason Miller and Republican National Committee spokesman Sean Spicer announced anyone being vetted for a high post in the administration must provide a termination of lobbying form if they are a registered lobbyist.

In addition, when officials leave the government, they will be banned from being a lobbyist for five years as part of the agreement to serve in Trump's administration.

"Not only will people will not be able to registered state or federal lobbyists, but when they leave government, they will be banned from being a registered lobbyist for five years," Spicer said.

"Why that is crucial is that it goes back to Mr. Trump's goal of making sure that people aren't using the government to enrich themselves and using their service in government to do that," he added.

Why hasn't Trump's transition team called the Pentagon?

President Barack Obama imposed a two-year lobbying ban for officials who left his administration, a policy instituted by executive order on his first day in office.

Any ban on lobbying, however, depends on how it is written and enforced. A common practice in Washington is for key power players not to register as a lobbyist, but instead work as a consultant or adviser -- allowing them to take their experience and contacts to make hundreds of thousands of dollars on K Street.

The announcement comes as Trump's transition team works to remove lobbyists from its ranks after Vice President-elect Mike Pence took over the efforts from New Jersey Gov. Chris Christie.

The transition operation working before Election Day was staffed with long-time Washington experts and lobbyists from K Street, think tanks and political offices, drawing questions about Trump's commitment to reforms.

On "60 Minutes" Sunday, Trump acknowledged the transition team was stacked with DC insiders.

"Everybody's a lobbyist down there," he said.

"That's the problem with the system -- the system," Trump said. "We're doing a lot of things to clean up the system. But everybody that works for government, they then leave government and they become a lobbyist, essentially. I mean, the whole place is one big lobbyist."

Trump said relying on lobbyists now while planning to eliminate them later is no contradiction.

"I'm saying that they know the system right now, but we're going to phase that out. You have to phase it out," Trump said.