The BBC is to publish new guidelines under which it could suspend employees' Twitter accounts, the new director-general has said.
Tim Davie said the rules would cover those working in news, current affairs and beyond and were "imminent".
He was appearing before a House of Commons committee to answer questions on a number of issues facing the BBC.
Mr Davie said: "We are going to be publishing in the next few weeks, and this is imminent, clear social media guidelines, and they will cover both news and current affairs, and beyond news and current affairs.
"We will have, within those guidelines, the enforcement policies will be very clear.
"We will be able to take disciplinary action. We will be able to take people off Twitter. I know people want to see hard action on this."
He added: "If they want to work for the BBC, I can ask people, you would suspend their Twitter account, absolutely."
He also commented on sports presenter Gary Lineker, who it was recently revealed has just signed a new five-year contract with the broadcaster, with a 23% pay cut - from £1.75 million to around £1.35m.
Mr Lineker has dismissed suggestions he has been asked to tweet more carefully.
Addressing the issue, Mr Davie said: "I would note that Gary Lineker has actually been very clear in his statements recently, saying 'I understand I have responsibilities when working at the BBC'.
"Those responsibilities will be clearly laid out and my belief is, as I say, I am now the director-general so I am running the show, and in my view party political statements are not the right thing for people to be making if they are, as part of an impartial news organisation.
"I mean, we will come back with social media guidelines to make clear where the lines are.
"If someone is a face of the BBC I think entering into party politics seems to be not the right place to be and I've been very clear about that."
Mr Davie later added: "The good thing is I will be making that even clearer as I go through my social media guidelines."
Asked whether the BBC might axe its traditional television channels, Mr Davie said: "I suspect over the long-term linear consumption will be down, so you might see a reduced number of linear channels, but certainly we are miles away from that."
He also said the broadcaster may aim to secure less of its viewers' time in the future.
Mr Davie said: "I'd be very blunt. I think you can take maybe less hours of someone's time. But what you do do is make them count. And we all know that, in the BBC Radio where it is strong enough.
"I don't think the BBC needs necessarily 40 hours a week of someone's time. But if it is an important eight hours or an important 10 hours.
"So that's part of my push to say: 'Don't try and battle this to your point by doing more and more and more and trying to replicate everything."
Mr Davie highlighted natural history, "proper current affairs" and entertainment formats that help procure young talent as important areas.