China's post office is hoping to boost business by allowing customers to send letters postmarked from space.

Emails will be sent to a computer aboard Tiangong-1, a spacecraft currently orbiting the earth, and rerouted to a special China Space Post Office branch on the ground in Beijing, the country's space programme said on its website.

The emails will then be printed, placed in space-themed envelopes, stamped with a new galactic postmark and sent on in the mail.

The gimmick, which features China's first astronaut, Yang Liwei, as head of a so-called "space post office", is the latest initiative devised by the postal service to drum up business as more and more Chinese go online.

Last year, it launched a service that allows people to send letters in sturdy envelopes to be delivered in the year 2020.

The Tiangong-1 unmanned spacecraft launched in September as part of China's ambitious plans to set up a manned space station by 2020.