SAN FRANCISCO - Sundar Pichai, the chief executive officer of Google, has acknowledged that it has been "a very difficult time" since a memo challenging the technology company's diversity policies was circulated over the past week.

His statement, which was sent on Monday night in a note by email to employees and posted on Tuesday on the website of the subsidiary of Alphabet Inc, came out the same day when the author of the memo, a 28-year-old male software engineer, was fired.

However, Pichai did not mention the name of the engineer and his dismissal from Google, which is headquartered in Mountain View, California.

In his 10-page memo, James Damore cited "possible non-bias causes of the gender gap" in the technology industry, including "personality differences" between men and women, and alleged that Google has created discriminatory practices with its hiring policies, such as "programs, mentoring, and classes only for people with a certain gender or race".

One of the so-called "personality differences" listed by Damore in the memo is what he called "neuroticism" among women, elaborated as "higher anxiety, lower stress tolerance".

In his response, Pichai said "much of what was in that memo is fair to debate, regardless of whether a vast majority of Googlers disagree with it", but portions of the writing "violate our Code of Conduct and cross the line by advancing harmful gender stereotypes in our workplace," adding that "to suggest a group of our colleagues have traits that make them less biologically suited to that work is offensive and not OK".

Saying some employees are hurting because of the memo, the CEO noted that the company expects "each Googler to do their utmost to create a workplace culture that is free of harassment, intimidation, bias and unlawful discrimination."

Meanwhile, he wrote that the memo's author had the right to express his views on topics such as Google's training, the role of ideology in the workplace, and whether programs for women and "underserved groups" - a reference to some ethnic groups, such as African Americans and Latinos - are sufficiently open to all groups.

Xinhua