MILAN, April 22 (Reuters) - Italian energy contractor Saipem said on Monday its first-quarter adjusted core earnings rose 40% on the same period of last year, driven by growth at its offshore engineering and construction business.

Adjusted core earnings increased to 268 million euros ($285 million) from 191 million euros in the same period of last year.

The group said its most significant new contract in the first three months of the year was the execution of the Whiptail oilfield development project for ExxonMobil offshore Guyana.

($1 = 0.9392 euros) (Reporting by Francesca Landini; Editing by Jan Harvey)