More than a quarter of Londoners believe a Kent town is part of the capital, according to a new YouGov poll.

It's sometimes joked everything inside the M25 belongs to the capital whereas those areas falling outside the orbital ring count as another country altogether.

However, Dartford which lies 18 miles south-east of central London but operates independently of City Hall is the exception to the "rule" with some of its citizens living inside the motorway's confines and others just outside.

But perception of its status as a Kentish town was thrown into doubt this week after a new YouGov survey appeared to suggest otherwise.

The new poll quizzed 1,145 London adults on whether they considered 12 places to be part of the city.

Dartford narrowly retained its independence in the eyes of Londoners with a majority (52%) believing it not to be part of the capital, however 28% reported they believed it was in fact an extension of the city.

The responses raised a few eyebrows among local people on Twitter who queried the sample polled.

Across the Thames from Dartford, Thurrock in Essex is seen as outside the capital’s clutches, by 60% to 9% who think is is in London.

But London's march into Essex has seen Barking and Dagenham adopted as fully fledged members, with 65% and 50% of those polled believing the areas to be part of London, respectively.

The north Kent town has so far fended off advances to be adopted as part of the Greater London Assembly, which includes the previous Kent towns of Bexley and Bromley.

In 2005 the then London Mayor Ken Livingstone suggested Dartford should be allowed to vote to join the capital and take advantage of some of the benefits such as free travel for under 18s.

Although the Oyster zip card scheme is among those entitlements which could be scrapped as part of the planned Transport for London bailout package.

No such breakaway has yet come to fruition but the topic was mooted again in 2015 when a London School of Economics professor predicted the "economic reality" of Dartford being absorbed into London would happen by the end of the 2020s.

Dartford council leader Jeremy Kite dismissed the idea as "rubbish" at the time.

His view is shared by Dartford MP Gareth Johnson who has also previously spoken out against attempts to bring Dartford under London control.

In a column for the Dartford Messenger he wrote: "I have always maintained that we should protect our Kentish identity that is separate from London."

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