BRUSSELS (Reuters) - EU antitrust regulators are unlikely to seek feedback to remedies offered by the European Energy Exchange last week to address concerns about its Nasdaq deal, a sign that these are insufficient, sources with direct knowledge of the matter said on Monday.

EEX, which is part of Deutsche Boerse, is seeking to acquire Nasdaq's European power trading and clearing business Nasdaq Power, whose platforms are of key significance for users and businesses in the Nordics.

It submitted remedies to the EU on May 27.

The European Commission, which acts as the EU competition enforcer, is expected to open a full-scale investigation into the deal following the end of its preliminary review on June 26 unless EEX beefs up its remedies in the coming days, the people said.