Transport Secretary Patrick McLoughlin said today is a "very important day" for Derby-based train maker Bombardier.
The firm signed a £180 million deal to provide another 116 carriages for Southern, to be used on services through London.
In 2011, the company lost out to German firm Siemens to build new train carriages for its Thameslink route.
Speaking today Mr McLoughlin said: "I think Bombardier have put it behind then, there was disappointment and I shared that disappointment but there was an open process, an open contract, they didn't win that particular one."
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Any remaining showers will soon clear leaving a dry night.
Early evening sunshine in places but, overnight, mist and low clod will move back in from the east, giving fog and drizzle in places.
Visibility will be poor again overnight and tomorrow with mist and fog rolling in from the North Sea. However it is also warming up!