As Theresa May kicks off the process of Britain's withdrawal from the EU with a plea for "unity", a new poll has suggested that the UK remains split down the middle on the issue, with 44% saying the decision to leave was right and 43% wrong.

But the YouGov survey found little appetite for a second referendum on the deal the Prime Minister secures in Brussels, with just 21% backing the idea, against 25% who did not support Brexit but believe Mrs May should implement the referendum decision and 44% who want Britain to leave.

Some 37% said the Government has been handling the Brexit negotiations badly so far, against 35% who think it is doing well. More than a third (35%) said Mrs May had been moving too slowly, compared with 20% who said she was going too quickly and 27% that she had got it right.

Almost half (48%) said they had confidence in the PM to negotiate the kind of deal she wants from Brussels, while 39% did not.

As Chancellor Philip Hammond warned that it will not be possible for the UK to "have our cake and eat it", there were signs that voters are still hopeful of maintaining free trade with the remaining EU while at the same time imposing controls on immigration.

Despite expert warnings that the EU will not allow full access to the single market without free movement of people, some 40% said it was a "false choice" and Britain would be able to get its way on both.

If forced to choose between the two priorities, respondents were split evenly 42% to 42% over whether they would prefer control over EU immigration or tariff-free access to the single market.

The 2,000 people questioned for the poll had a gloomy view overall of Brexit's likely impact on the UK, with the largest number saying it would be bad for the economy (37%, compared with 27% saying it will be good), Britain's influence in the world (35%-19%), jobs (34%-24%) , the NHS (28%-27%) and pensions (25%-8%).

But a clear majority (49%) said it would result in lower immigration into Britain, compared with just 3% who said it would increase numbers of migrants and 33% who said it would make no difference.

The most widely-feared negative impacts from Brexit were inflation in the shops (30%), less foreign investment (25%) and barriers to exports (23%), while the most anticipated benefits were freedom to trade with countries outside the EU (30%), cuts in immigration (24%) and more money for public services (19%).

In a stark indication of the depth of divisions in opinion, 37% of Leave voters said they expected no negative impacts at all from Brexit, while 35% of Remain voters anticipated no positive results.

:: YouGov questioned 1,957 adults on March 26 and 27.