A vaccine shown to be 100% effective against two virus strains that cause most cervical cancer could be available within a year, say manufacturers.
Gardasil worked against the sexually transmitted human papillomavirus (HPV).
Some 12,167 women aged 16 to 23 from 13 countries, including the UK, took part in the drug company study.
Researchers believe a vaccine could work best if given before adolescence, but critics fear this could encourage under-age sex.
Merck's vaccine is in head-to-head competition with a rival from UK-based GlaxoSmithKline called Cervarix.
Cervical cancer kills 274,000 women worldwide every year, including 1,120 in the UK.
The two-year Future II trial found Gardasil was 100% effective at preventing early stage cancers and pre-cancerous abnormalities caused by the two key strains of HPV - the 16 and 18 strains - which cause 70% of cervical cancers.
Similar results were previously seen in a smaller trial of 277 women.
These results add to the mounting evidence that cervical cancer vaccines offer great promise for the future
Dr Anne Szarewski, Cancer Research UK
Dr Anne Szarewski, clinical consultant at Cancer Research UK, said: "These results add to the mounting evidence that cervical cancer vaccines offer great promise for the future.
"It appears we may soon be able to prevent the majority of cases. With any disease caused by a virus, the best way to stop it is to prevent it with a vaccine."
However, she said a woman should remember that an abnormal smear result does not necessarily mean she will go on to get cervical cancer. Many abnormalities get better on their own and disappear.
Also, she said it would take many more years to know whether a vaccine continued to offer long term protection and that it was therefore essential to continue with cervical screening - women attending for regular smear tests.
Julietta Patnick, director of the NHS Cancer Screening Programmes, said regular cervical screening was the best way of preventing cervical cancer.
All women registered with a GP should receive their first invitation at 25 and then every three years until they are 49. Women between 50 and 64 will be invited every five years.
Cambridge University's Professor Margaret Stanley said: "The results of Future II are so exciting because of the sheer size of the trial and the fact that it demonstrated 100% efficacy."
Professor Peter Rigby, chief executive of the Institute of Cancer Research, was also excited by the findings.
He said: "Nearly 3,000 people in the UK are diagnosed with cervical cancer each year, so it is very exciting to hear it may be possible to drastically reduce this number in the foreseeable future."
Gardasil's manufacturers - Sanofi Pasteur and Merck & Co Inc - are expected to apply for a US Food and Drug Administration licence to market the vaccine before the end of the year.
This will be followed by a licence application to the European Medicines Agency.
Although HPV is transmitted through sexual intercourse, a vaccine is likely to be administered to girls as young as 10 to 13 - critics says this could encourage under-age sex.
Gardasil also acts against HPV strains six and 11 which cause genital warts.