Women have a harder time accessing work globally than previously thought, while the gender gap in working conditions and pay has barely budged in two decades, the United Nations said Monday.

The UN's International Labour Organization said it had developed a new indicator that does a better job than official unemployment rates at capturing all people without employment that are interested in finding work.

"It paints a much bleaker picture of the situation of women in the world of work than the more commonly-used unemployment rate," the ILO said in a statement, two days before International Women's Day.

"The new data shows that women still have a much harder time finding a job than men."

This, ILO said, is because the criteria used to determine if someone should officially be considered unemployed tend to disproportionately exclude women.

It pointed out that personal and family responsibilities, including unpaid care work, disproportionately affects women.

Such activities, it said, not only often prevent women from working, but also from actively searching for employment or being available to work on short notice, which are criteria for being considered unemployed.

The UN labour organisation found that the jobs gap was particularly severe in low-income countries, where nearly a quarter of women were unable to find a job.

For men, the corresponding rate was below 17 percent, ILO said.

Access to employment is not the only problem.

ILO highlighted that women tend to be overrepresented in certain types of vulnerable jobs, including helping out in relatives' businesses rather than being in own-account work.

"This vulnerability, together with lower employment rates, takes a toll on women's earnings," ILO said.

"Globally, for each dollar of labour income men earn, women earned only 51 cents."

The pay gap meanwhile varies widely between regions, with the figure dropping to 33 cents in low income countries, but reaching 58 cents in high-income countries.

"This striking disparity in earnings is driven by both women's lower employment level, as well as their lower average earnings when they are employed," ILO said.

According to new ILO data, 15 percent of working-age women globally would like to work, but do not have a job, compared to 10.5 percent of men.

"This gender gap has remained almost unchanged for two decades," it said.

By contrast, official unemployment rates for women and men are very similar.