A giant panda at Edinburgh Zoo is showing signs of pregnancy and could give birth within weeks to what would be the first cub from the rare species born in Britain, officials said.

The news was treated as a major story by British media and members of the public immediately drew comparisons with the recent frenzy over the birth of royal baby Prince George at St Mary's Hospital in London on July 22.

Giant panda Tian Tian was born in 2003 and arrived in Scotland two years ago on a 10-year loan from China. She was artificially inseminated in April after two failed attempts to mate naturally with the zoo's male, Yang Guang.

"We cannot tell definitively at this stage if Tian Tian is pregnant or not, although we are seeing results that give us cause for encouragement," said zoo CEO Chris West. "If there is a cub it could be born between late August and early September."

Giant pandas are one of the world's most endangered species. Their natural home lies in a few mountain ranges in central China. There are about 1,600 known to be living in the wild and some 300 in captivity, mostly in China.

Female pandas are able to conceive only for two or three days in the spring, which makes reproduction difficult. The gestation period is about five months.

It is notoriously tricky to tell whether a female panda is expecting a cub because the species is prone to "pseudo pregnancies" where the signs are very similar. Tian Tian has been displaying nesting behaviour, but that is not conclusive.

"An ultrasound did not prove possible as they are totally optional and Tian Tian chose not to participate," said West.

The zoo said that in addition to monitoring Tian Tian's hormone levels, the panda team were also employing and seeking to refine cutting edge acute protein analysis techniques pioneered by Memphis Zoo in the United States.

The results seemed to suggest the profile of a pregnant panda that will carry to full term, Edinburgh Zoo said.