Closing all of Parliament’s bars could lead to greater security risks for MPs, the leader of the House of Commons has suggested.

Lucy Powell said she was open to “having a debate” on the future of drinking venues on the Parliamentary estate after one bar was temporarily closed for a security review linked to an alleged drink-spiking incident.

But she argued that MPs and staff would visit venues outside Parliament’s secure zone if bars, restaurants, hair salons and other facilities were shut down.

She told BBC Radio 5Live’s Matt Chorley said “there is no point spending the millions of pounds” on security if staff were encouraged to leave the estate.

Parliament’s most famous pub, the Strangers’ Bar, is currently shut while police investigate a report a woman had her drink spiked on 7 January.

Powell said she was in favour of reopening Strangers following a review of its security arrangements.

“We definitely need to look at this and make sure we have the measures in place so that people are not in the situation where they think they have been spiked or showing the effects of being spiked,” Powell said.

She said she was open to having a public debate “on whether there should be any bars on the estate at all”.

But not all of the sprawling eight-acre (32,000 sq-m) Palace of Westminster is a workplace, she told Matt Chorley, and there were several venues serving alcohol for MPs and their guests.

She said she did not “get the sense that there’s a groundswell” of support for closing these down.

In the evening members of staff and others who “might want a drink” are “not at work at that point,” she argued.

She said they would MPs be less well protected attending venues “where they have not got the security protection”, she added.

“They have not got police around” and would also not be covered by the Independent Complaints and Grievance Scheme (ICGS) – which investigates allegations of sexual misconduct and bullying by parliamentary staff.

The ICGS has previously argued parliament’s bars and associated culture of drinking fuels inappropriate behaviour in Westminster.

Parliament had increased security “with good reason” because “there are a lot of people trying to attack MPs and attack Parliament” she said.

“That is why we provide services on the estate.

“There is no point spending the millions of pounds we spend keeping everyone secure and on this estate – if we then actually just encourage people to pop off to go and get their hair cut or have lunch with a journalist off the estate.”