The Australian Competition and Consumer Commission (ACCC) said that Ampol's (ASX:ALD) acquisition of EG Group Australia and EG AsiaPac Holdings requires "further in-depth assessment" by the regulator, and the transaction will move to a second phase review.

In a statement on Wednesday, the regulator said the acquisition would lead to a merger of major fuel retailers in Australia, adding that it identified 115 EG sites in the local market where the acquisition could "substantially" lessen competition.

The regulator said the issue can't be adequately addressed by Ampol's offer to divest 19 retail fuel sites.

The second phase review is expected to take up to 90 business days, unless extended.

In an Australian bourse filing on Wednesday, Ampol acknowledged that the regulator's decision was consistent with the new merger control regime process, saying that it remained confident in its position and that it will continue to work constructively with the ACCC during this phase. The transaction remains on track for anticipated completion in mid-2026.

The ACCC invited submissions in response to its phase 2 notice by Feb. 4.

Ampol's shares were down about 1% in recent Wednesday trade.