Mr Munro will present the medals and memorabilia to Motat at a handover ceremony this morning.
The presentation will take place in front of one of the few remaining examples of the Avro Lancaster Bomber, which was made famous as a successful night bomber by the RAF Bomber Command in World War II.
Prime Minister John Key will attended the presentation.
Lord Ashcroft said he was "delighted" his proposal was accepted by Mr Munro as it provided a 'win-win' situation for all concerned, and ensured the medals and memorabilia would remain in New Zealand for future generations to appreciate.
The medals were in Lord Ashcroft's care. He then flew with them to New Zealand to personally deliver them to Mr Munro so that he in turn could hand them to Motat's chief executive Michael Frawley at the ceremony.
"We are deeply grateful to Mr Munro for agreeing to this arrangement and the Museum is honoured to accept these precious items into its collection," Mr Frawley said.
"Motat has a close association with New Zealand Bomber Command and the utmost respect for the sacrifice and courage these men showed in the Second World War.
"It's our intention to develop an exhibition highlighting what Mr Les Munro, Mr Len Chambers and the other New Zealand members of Bomber Command, in particular 617 Squadron, did during the war."