New research suggests women are less likely than men to request a pay rise without prior encouragement - suggesting that Britain's gender pay gap could be attributable to employees', rather than employers' attitudes.
Previous studies have suggested that women are generally reluctant to negotiate higher salaries under all circumstances. However the new study from the University of Chicago suggests women are just as willing as men to demand more money, but only when they receive an invitation.
The study looked at people who responded to job advertisements, where salaries were either advertised as fixed or negotiable. The findings showed that women were three times more likely to apply for positions where the salary was up for discussion.
However, where the salary was fixed, 11 percent of men were sufficiently confident to begin salary discussions - compared to just eight percent of women.
John List, an economist and professor at the University of Chicago and co-author of the study, said: "We find that simple manipulations of the contract environment can significantly shift the gender composition of the applicant pool.
"By merely adding the information that the wage is 'negotiable,' we successfully reduced the gender gap in applications by approximately 45 percent."
The Chicago research follows a recent report by the Fawcett Society which said that women in the UK, on average, earn 14.9 percent less than men for the same job. The researchers warn that the pay gap could get bigger as public sector job cuts push women into the private sector - where the gender pay gap is even wider.
Past studies have indicated that men are nine times more likely to ask for a bigger salary when applying for job.
List said the gender gap in wages begins when a person is hired, so encouraging negotiations from the onset is likely to have a long-term impact on salary.
In the US, the average woman's pay is just 75 percent of the mean male salary, and just 2.5 percent of the highest-paid jobs are held by women.