A Japanese zoo has apologised after receiving complaints over naming a baby monkey Charlotte after the newborn British princess.

The Takasakiyama Natural Zoological Garden said it was considering renaming the macaque.

It was flooded with angry calls and emails hours after announcing the name for its first monkey born this year, a tradition at the zoo run by the southern city of Oita.

Charlotte came top in a public ballot, receiving 59 out of 853 votes before the female monkey was born on Wednesday.

Votes for Charlotte surged after the British princess was named on Monday and topped the ballot in the last three days of voting, which ran from March 27 to May 6.

Opponents said giving the princess's name to a monkey was disrespectful to British royals. According to zoo official Akira Asano, some of them said that the Japanese people would feel offended if a monkey were named after Japanese princesses.

The complaints originated in Japan. Mr Asano said he was not aware of any complaints from British citizens.

He said the zoo has also received support for Charlotte and views are now largely divided.

"We deeply apologise for causing trouble to many people over the naming of the first baby (monkey)," said a statement posted on the zoo website. "We take these opinions seriously."

Officials of the zoo and the city were still discussing what to do with the monkey's name.

The zoo now plans to seek advice from the British Embassy before making a final decision, Kyodo News agency reported.

The embassy declined to comment and Japan's foreign ministry said it was not involved with the issue.