BRUSSELS, July 1 (Reuters) - The European Commission said on Thursday it has reached a deal with Italy on the parameters for separating lossmaking carrier Alitalia from its successor, a step key to securing EU approval for the new airline and to write off Alitalia's subsidies.

"Following intense and constructive discussions at all levels, the Commission and the Italian authorities have reached a common understanding on the key parameters to ensure economic discontinuity between ITA and Alitalia," a Commission spokesperson said.

(Reporting by Foo Yun Chee; editing by Jason Neely)