(Corrects to show replacements will report to Luc Machiels, paragraph 7; paraphrases paragraph 4 to clarify that positions will be filled on an interim basis)

NEW YORK, Feb 5 (Reuters) - Two senior executives in the U.S. energy trading unit of Dutch-Belgian financial services group Fortis (FOR.AS: Quote, Profile, Research) (FOR.BR: Quote, Profile, Research) have resigned, a company spokeswoman said on Tuesday.

David Jones, U.S. head of global oil at Houston-based Fortis Energy Marketing & Trading (FEMT), and Jack Farley, the unit's managing director and head of power trading, left their jobs on Tuesday, the spokeswoman said.

"It's a realignment that's been continuing since changes we announced at FEMT in October," the spokeswoman said.

She said Jones' and Farley's jobs would be filled on an interim basis.

FEMT was created when Fortis acquired Cinergy Marketing & Trading from Duke Energy in late 2006. Fortis had announced in October that FEMT President Jim Fallon would step down on Dec. 31, 2007.

The spokeswoman said Jones' job will be assumed by Fortis' global head of oil trading, Michael Selman.

Farley's responsibilities will be overseen by Lloyd Jackson, another FEMT executive.

Both will report to FEMT managing director and president Luc Machiels.