Jeremy Corbyn has said the Army should not have to be deployed on Britain's streets to respond to the terror threat because there should be enough police officers to protect people.
The Labour leader also said it was "disturbing" that armed police will be guarding hundreds of events over the bank holiday, but stressed the need to protect people.
More than 1,000 armed officers have been positioned around the country this weekend in the wake of the Manchester Arena atrocity, with the terror threat level at "critical" - meaning an attack is imminent - while troops have been stationed at key potential targets.
As the Government's Cobra emergency committee met, the Labour leader said he wanted to see the threat level reduced as quickly as possible as long as it was safe to do so.
Asked if he supported the deployment of armed police, including at the FA Cup Final at Wembley, which he will attend, Mr Corbyn said: "I find it disturbing, everybody finds it disturbing, but we have to make sure we're safe.
"I will obviously look into the situation and hope we can reduce the threat level as quickly as possible.
"We want people to be safe, we want people to enjoy a bank holiday, which is what a bank holiday is for, and we need to be secure and I think there's a balance to be drawn there.
"The balance has to be that it's police who do it, rather than the Army, but it's also about the strength of our communities.
"Let's come together in adversity, not divide ourselves."
Mr Corbyn said he was "concerned" that Army troops have been drafted in to protect certain potential targets, blaming the move on a shortage of police officers due to Tory cuts.
"I am concerned that the Army has now been deployed and protecting some installations in places, mainly because of the shortage in police numbers," he said.
"A Labour government has pledged absolutely clearly it will employ 10,000 more police, not less police. We need police to keep us safe, but we also need to deal with the appalling incident in Manchester, and find all those that were culpable in doing it.
"But also as a response, come together as communities and that was the message that came out of that huge turnout of very defiant people in Albert Square in Manchester only 18 hours after the attack."
Mr Corbyn also insisted his speech on Friday linking British military intervention abroad with terror at home was not about the Manchester attack.
"I did not suggest there were links between the attack and that (foreign policy)," he said.
"What I said was the attack was horrendous, awful and was mass murder.
"What I said was we have to be serious about the situation that exists in Libya and other countries and a sensible government would also be looking at the international situation - ungoverned spaces in Libya are a danger to all of us."
He added: "I want us to put all our efforts into trying to build a process in Libya (so) that people can lead secure lives and refugees can also gain some safety, either in the refugee camps or, hopefully, ultimately to be able to return to their homes.
"If we leave it as it is, it's going to be a place where all kinds of terrible ideas are going to gain traction out of desperation."
Ukip leader Paul Nuttall said troops had been on the streets of Brussels, where he works as an MEP, since Belgium was hit by terrorist attacks.
"No-one really wants to see the Army on the streets and I do think that the cuts in terms of police officers should be reversed - in our manifesto we talk about 20,000 new police officers, and what we really want to see are bobbies on the beat, not the Army," he told the Press Association.
"However, when the terror threat is raised then it makes sense to have the Army on the streets - but it's not something we want to see on a regular basis."