The proposed acquisition of travel company Stella Travel Services may raise competition concerns, the Australian Competition and Consumer Commission (ACCC) says.

Under the deal announced in May, Jetset Travelworld would acquire Australia-based Stella, with Stella shareholders to hold 50 per cent of the capital of the entity. Jetset is listed on the ASX with Qantas having a 58 per cent stake.

Stella's brands in New Zealand include United Travel, Harvey World Travel and Go Holidays.

Jetset and Stella were each other's closest competitors, ACCC said yesterday.

It said the removal of each other as an alternative for retailers seeking affiliation to a network may increase the influence the merged firm has.

When the companies announced the proposed deal, they said the merged entity would be well positioned to explore further growth opportunities.