Shell buys into gas assets in Ukraine
Regal owns licences for developing two fields with reserves of almost 170 million barrels of oil equivalent.
In the next eight weeks Shell will hold talks on investing in the project. Analysts say up to $US 360 million will be needed.
British oil firm MND signed an agreement for the fields with Regal in September, but the deal expired without coming to fruition.
Shell is already exploring eight fields near Poltava and Kharkov in Ukraine.