July 10 (Reuters) - Hong Kong conglomerate CK Hutchison is reviewing options for its European telco unit with a view to reducing its holdings in the overall business, six people with knowledge of the situation said.

In reviewing its options as recently as this year, the ports-to-telecoms conglomerate has discussed a potential spin-off with a view to IPO its European telecoms assets, three of the people said, a sale of the unit as a bloc, a fourth person said, or continuing being open to selling controlling stakes in some countries, a fifth person added.

CK Hutchison Group Telecom operates the 3 networks in Italy, the UK, Sweden, Denmark, Austria and Ireland.

CK Hutchison's main focus currently has been country by country solutions to enhance the group's returns, according to two of the sources. An IPO of the European business is also seen as difficult due to market conditions, one of the sources said.

The deliberations over the assets are at an early stage, the sources cautioned.

One of the people added the company is trying to revive an aborted deal to spin off and cede control of its wholesale mobile and fixed network operations in Italy.

It has also been looking to divest its business in Denmark and Sweden by forming mergers with third parties but none of the negotiations have resulted in a deal yet, the person said.

All six sources spoke on condition of anonymity because the talks are private.

"We do not comment on market speculation. As management mentioned recently at our Annual General Meeting, the group will continue to pursue value accretive transactions," CK Hutchison said in a statement to Reuters.

The deliberations have occurred as European telecoms operators grapple with lower returns partly linked to the high investment needed to upgrade their network infrastructure in a crowded market in which players are looking to consolidate.

In the past couple of years, the group has told investors in-market consolidation and "asset-light" remains its strategy for its telecommunications business.

CK Hutchison last year announced a 15 billion pound ($19 billion) merger with Vodafone of their British mobile operations, in which it would own 49%. The deal is still being scrutinised by the local antitrust regulator, which is expected to reach a decision by the end of year.

CK Hutchison's Europe telecom business reported a 9% drop in earnings before interest, taxes, depreciations and amortisation (EBITDA) last year to 2.5 billion euro. Its revenue rose 1% to 9.4 billion euros.

The people said no deal appeared to be imminent over its European assets, with some of them saying CK Hutchison will likely wait for the outcome of the antitrust review of the Three-Vodafone merger in the United Kingdom before taking any action. (Reporting by Amy Jo Crowley in London, Kane Wu and Clare Jim in Hong Kong and Elvira Pollina in Milan, editing by Anousha Sakoui, Alexandra Hudson)