Actor Ralph Fiennes has promised to devote as much of his time as possible to helping the United Nations' children's charity Unicef.

Fiennes, currently starring in the Oscar-nominated The End of the Affair, made his pledge at the London launch of a Unicef campaign to raise awareness of the millions of children worldwide who are forced to grow up alone.

"My interest in Unicef was probably sparked off last year, when I was part of a Unicef fundraising event for Kosovo and was very impressed with the way it was organised," explained Fiennes.

He continued: "I hope to have an ongoing involvement in Unicef as long as they will have me, but obviously I have work commitments so I will have to just do the best I can."

The Unicef report Growing up Alone focuses on the three main reasons why children find themselves alone: poverty, HIV/Aids and war.

The 37-year-old actor said he had been particularly moved by his recent visit to Romania on Unicef's behalf.

Lottery element

During his trip he met children who had been placed in institutions by their families because they did not have enough money to feed and clothe them, or because of family breakdown.

"The most moving thing I found is that, whatever the lack of material resources around the children, the spirit inside them has not died," he recalled.

"It's upsetting to feel that we should talk about luck and that life should be a sort of lottery. I would like to think that this campaign takes away the lottery element."

Fiennes said he had been shocked by the effect on families left by the regime of the former dictator Nicolae Ceausescu.

He said people were so reliant on the state that in times of dire need they simply "delivered" their children to institutions.

Unicef chief executive David Bull said: "This trilogy of tragedies which lead to children growing up alone demands that we act now.

"At the dawn of the new century we must seize the opportunity to renew our commitment to children and reverse the current trend of increasing inequality which threatens the future of so many young lives."