The sale of tobacco worldwide should be phased out by 2040, public health researchers have insisted.

The international group of health and policy experts claim that with sufficient political support and increased action against the tobacco industry, a tobacco-free world - where less than 5% of adults smoke - could be possible within the next three decades.

They noted that by the end of this century, one billion people will have died as a result of tobacco use if efforts to tackle this problem are not accelerated.

The majority of these deaths will be in low and middle-income countries.

"The time has come for the world to acknowledge the unacceptability of the damage being done by the tobacco industry and work towards a world essentially free from the legal and illegal sale of tobacco products.

"A world where tobacco is out of sight, out of mind, and out of fashion - yet not prohibited - is achievable in less than three decades from now, but only with full commitment from governments, international agencies, such as the UN (United Nations) and WHO (World Health Organization), and civil society," commented lead researcher, Prof Robert Beaglehole, of the University of Auckland in New Zealand.

The Irish Government has already committed to creating a tobacco-free Ireland by 2025. In 2013, it launched a new tobacco policy, Tobacco Free Ireland, which contains over 60 recommendations aimed at de-normalising smoking in Irish society.

The international experts' views were published in the medical journal, The Lancet. Meanwhile, in an accompanying research article, Japanese researchers pointed out that while rates of smoking are declining slowly overall, smoking prevalence is expected to increase in some countries over the next decade, particularly in the Middle East and Africa.

They noted that as the world's population is increasing , there will still be one billion smokers by 2025 unless there is a major acceleration of action against tobacco use.

The researchers acknowledged that some countries have ‘led the way in implementing strong tobacco-reduction policies', including Ireland, Scotland and Australia. However, they insisted that global tobacco regulation must now be ‘turbo-charged'.

They pointed out that the supply of tobacco is dominated by four major international companies, known as the ‘big four'. As smoking prevalence has fallen in high-income countries, these companies are now turning their attention to low and middle-income countries using tactics such as sponsorship of events aimed at females or young people.

"Contrary to industry claims, tobacco marketing deliberately targets women and young people. The tobacco industry continues to interfere with governments' efforts to implement effective tobacco control policies.

"If the world is to become tobacco free, it's vital that the industry's appalling conduct receives far closer scrutiny and countries which stand up to the industry's bullying tactics receive better global support," commented Prof Anna Gilmore of the University of Bath in the UK.