There will be some assistance for people unable to queue for a long stretch of time to see the Queen’s lying in state, Downing Street has said.

Members of the public wishing to make the journey to Westminster Hall have been urged to plan ahead, with queue times expected to stretch on for hours – including through the night – as people file past the late monarch’s coffin to pay their respects.

No 10 has said the “overarching aim” is to ensure “as many people as possible are able to come into London during this time”.

But with visitors warned they will have very little opportunity to sit down, as the queue will be continuously moving, questions have been raised over the accessibility of the occasion.

On Tuesday, the Prime Minister’s official spokesman said “everything possible” would be done to facilitate those who may not be able to wait for a long period of time.

“A lot of people understandably will want to see the lying in state and we will do everything possible to facilitate as many people as possible, including those who may not be physically able to wait that long, because of disabilities, for example,” he said.

Further guidance is expected to follow from the Government.

The spokesman said he is not aware of any “upper cap” on the number of people able to see the coffin.

“Those sorts of decisions (will) really (be) made by those on the ground once we see the scale of people who are attending,” he said.

Asked if there is a maximum total capacity for the occasion, he said: “If there is, I’m not aware of a number.

“I mean, I wouldn’t get into detailed operational planning… but I’m not aware of there being some sort of upper cap.”

The lying in state opens to the public at 5pm on Wednesday and will be accessible 24 hours a day until it closes at 6.30am on Monday September 19 – the day of the Queen’s funeral.

The queue route is understood to stretch from Victoria Tower Gardens across Lambeth Bridge down to Westminster Bridge, before veering right then left down Belvedere Road, through Jubilee Gardens back to South Bank and along to the Tate.

After the Tate, it is unclear where it will flow from.

People will not be allowed to camp and will be given numbered wristbands to indicate their place in the queue so they are able to leave and come back.

As large crowds are expected, there are likely to be road closures and delays on public transport.