He has met a number of senior representatives from the Unite union and local MPs of the Luton plant before flying to Germany.
There, Lord Mandelson is due to meet senior Chancellery officials and Economics Minister Karl-Theodor zu Guttenberg. He is also due to hold talks with Magna, the preferred bidder for GM Europe.
The UK government has been working closely with all the parties involved for months to set up a long-term capital structure for GM Europe including the UK operations in Luton and at Ellesmere Port on Merseyside.
Lord Mandelson said: "The government is continuing to do all it can to secure the future of production at the Luton and Ellesmere Port plants.
"The UK government is at the heart of the discussions on securing a commercial solution for GM Europe. I continue to fight for the best interests of all Vauxhall’s workforce in the UK."