Brad Pitt gave Angelina Jolie his great-grandmother's wedding ring to wear on her trip to Africa.

The 'Salt' actress decided to remove her £250,000 engagement ring for her recent UN visit to the Congo and Rwanda because she didn't want to be ''ostentatious'' and shortly before she flew out, her fiancé surprised her by giving her the plain gold band to wear instead.

A source said:'' She said she didn't want to wear her engagement ring because she thought it was important not to be ostentatious with clothes and jewellery when in a poor region.

''Brad said he completely understood why she couldn't wear her engagement ring, but he really wanted to give Angelina something special and more understated to wear instead. Angelina seemed truly touched by the special gift of his great-grandmother's wedding ring, and it meant a lot to be able to take it on the trip with her.''

According to insiders on the trip, Angelina - who raises six children with Brad - was enamoured by the replacement ring.

The source added to Grazia magazine: ''She couldn't stop playing with the replacement ring, which everyone was calling the 'trick ring'.''