Iain McNicol, the Labour Party general secretary, has laid a wreath at the Yad Vashem Holocaust memorial in Jerusalem on behalf of the party.
Mr McNicol travelled to Israel this week on a three-day visit organised by Labour Friends of Israel.
The trip was arranged after Isaac Herzog, Israeli Labour Party chairman, invited Jeremy Corbyn, Labour leader in the UK, to visit Yad Vashem, and Mr Corbyn turned down the offer. He said he was too busy to go.
Tom Watson, Mr Corbyn’s deputy leader, went to Jerusalem last November and also laid a wreath at the memorial.
Mr McNicol’s visit included meetings with leading Israeli Labour figures, sessions on entrepreneurial skills with Israeli and Palestinian youngsters, and tours of the Old City and Knesset.
Mr McNicol said: “I was deeply honoured to lay a wreath at Yad Vashem on behalf of the Labour Party; vowing never to forget the darkest moment in human history.
"It's always a pleasure to meet with colleagues from our sister party and I was delighted to meet the new Israeli Labor Secretary General, Eran Hermoni, as well as International Secretary MK Hilik Bar and MK Michal Biran.
“I'd like to thank LFI for organising this visit and for the vital work they do to bring our two sister parties together in a spirit of friendship and solidarity."
Jennifer Gerber, LFI director, said: “I'm delighted to bring Iain McNicol to Israel to demonstrate more fully the complexities of the region.
“For supporters of Israel in the Labour Party, it was incredibly heartening for Iain to visit with us and re-affirm Labour's commitment to a two-state solution."