A huge number of British children are taken by one of their parents to an overseas country, including India and Pakistan, and never returned, officials said Thursday.

The number of British children 'abducted' by a parent and taken overseas has risen by 39 percent in 2009, the child abduction department of Britain's Foreign and Commonwealth Office (FCO) said.

The department handled 146 cases of children taken to countries not covered by the 1980 Hague Convention on international child abduction, compared to 105 in 2008, The Independent reported.

The countries include India, Pakistan, Thailand, Ghana and Nigeria, which have not ratified the convention.

The highest number of 'abductions' take place in summer, when a parent takes a child on holiday to a country where they have relatives, and then refuses to bring them home, the FCO report said.

'If a parent wishes to take their child to live in a new country they will normally need either the permission of the other parent or British courts,' Foreign Office minister Jeremy Browne said.

'International parental child abduction, whether intentional or not, can cause huge distress to families.'

Cases where British nationals return to the country with their child following the breakdown of a relationship while the family is living abroad are also likely to be treated as abduction, he said.