The message was reported by local media, including on the official Weibo of China Newsweek, and coincided with the Qixi festival on Aug 22, also known as China’s Valentine’s Day, a traditional holiday celebrating love and romance.

The message was sent by Xian’s health commission and Xian’s family planning association.

Both government departments did not immediately respond to requests for comment.

Reuters was not able to independently verify the message.

“Continue the blood of China and share the important task of rejuvenation,” the Weibo post on China Newsweek read.

It added that marriage and childbearing should be done at the “right age” but did not give further details.

The message comes as Beijing tries to encourage young couples to have children, as an increasing number of women put off having children or opting to have none at all.

Many women cite the high cost of childrearing, difficulty in continuing on their career, gender discrimination and not wanting to get married as key factors for not wanting children.

Official rules in China make it hard for single or unmarried women to have children out of wedlock but some provinces like Sichuan in the southwest have started liberalising laws in the past year to boost fertility levels.

Concerned about China’s first population drop in six decades and its rapidly ageing population, the government’s political advisors proposed in March that single and unmarried women should have access to egg freezing and in vitro fertilisation (IVF) treatment, among other services.