The UK is "now seeing a second wave" of Covid-19, Prime Minister Boris Johnson has said, adding: "It's been inevitable we'd see it in this country.".

Mr Johnson said he did not "want to go into bigger lockdown measures" but that tighter social distancing rules might be necessary.

The first tier would be the level of measures currently in place in most parts of England now - with social distancing the key aspect.

The second tier would involve what is currently being imposed in north-east of England - curfews on hospitality venues and a ban on meetings between households.

The final third tier would involve stricter lockdown measures.

London Mayor Sadiq Khan said it was "increasingly likely" that the nine million people in the capital will need to follow areas such as the north-east of England and come under additional measures.

Earlier, BBC political editor Laura Kuenssberg said the government was considering a short period of tighter rules across England that could be announced in the next week, which could involve closing hospitality venues.

"Clearly when you look at what is happening, you've got to wonder whether we need to go further than the rule of six that we brought in," the prime minister said, referring to measures introduced on Monday.

Speaking in Oxfordshire, Mr Johnson said the government would keep "everything under review" but a second national lockdown was "the last thing anybody wants".

The government has also been considering what it called a "circuit-break" approach, which could involve re-introducing restrictions in public spaces for a period of a few weeks to suppress the spread of the virus