The number of alcohol breath tests deployed by police on England's roads has fallen by a quarter in the last five years, a new report has said.
ThThe figures, published by the Institute of Alcohol Studies on Friday, also show the number of Roads Policing Officers employed by English police forces fell by 27% between 2011/12 and 2015/16.
Roads Policing Officers are responsible for patrolling motorways and main roads.
Some forces have lost more than 83% of these officers since 2011, the report said.
If the use of alcohol breath tests - used by police to test whether a driver is drunk - had been maintained at its 2011 level, the report said, more than a quarter of a million (260,681) more breath tests would have been used.
The report pointed to a cut in police budgets to explain the decline. On average, the budget for policing roads has fallen from £5.3m to £4.35m since 2011 for each of the 18 forces who supplied data, the report said.
The institute called for the introduction of random roadside breath-testing to tackle the problem, and asked the government to launch mass media campaigns to properly explain the dangers of drink-driving to the public.
It also repeated its call for the drink-drive limit to be lowered from its current level of 80mg of alcohol per 100ml of blood to 50mg/100ml, which would put England and Wales in line with the rest of Europe, including Scotland and Northern Ireland.
Katherine Brown, chief executive of the Institute for Alcohol Studies, said: "While budgets continue to be squeezed, approximately 200 lives are being lost on our roads to drink-drivers every year.
"Although the Department for Transport says that is '200 too many', stripping police forces of the resources needed to tackle drink-driving may lead to worse outcomes in the future."
"Where enforcement levels are on the wane, more public campaigns would raise awareness about the dangers of drink-driving, and a lower drink drive limit would provide a cost-effective way of limiting the risk of people getting behind the wheel after consuming alcohol."
Pete Williams, from RAC Road Safety, added: "Falling road traffic police officer numbers are stretching forces and one impact of this appears to be a reduction in breathalyser tests which is a worrying development."
"RAC research has found that around five million drivers believe they have got behind the wheel while over the limit at least once in the past year."
"Our research also found there is extensive general public support for a UK-wide reduction in the legal blood-alcohol limit to 50 milligrams - as enforced in Scotland - or even to 20 milligrams, with six in 10 (59%) British motorists saying they are in favour of this becoming law."