BRUSSELS, April 30 (Reuters) - Meta Platforms' ( META )

Facebook and Instagram have failed to tackle disinformation and

deceptive advertising in the run-up to European Parliament

elections, the European Commission said on Tuesday as it opened

an investigation into suspected breaches of EU online content

rules.

The move by EU tech regulators came amid concerns about

Russia, China and Iran as potential sources of disinformation,

but also inside the EU, with some political parties and

organisations seeking to attract voters with lies in the June

6-9 vote to select the next five-year parliament.

The Digital Services Act which kicked in last year requires

Big Tech to do more to counter illegal and harmful content on

their platforms or risk fines of as much 6% of their global

annual turnover.

The EU investigation will focus in particular on a

Russia-based influence operation network dubbed Doppelganger

which clones authentic media and was exposed by Meta in 2022,

people familiar with the matter said. Meta says it has blocked

tens of thousands of links connected to it.

"We suspect that Meta's moderation is insufficient, that it

lacks transparency of advertisements and content moderation

procedures," EU digital chief Margrethe Vestager said in a

statement.

"So today, we have opened proceedings against Meta to assess

their compliance with the Digital Services Act," she said.

Meta, which has more than 250 million monthly active users

in the European Union, defended its risk mitigating process.

"We have a well established process for identifying and

mitigating risks on our platforms. We look forward to continuing

our cooperation with the European Commission and providing them

with further details of this work," a spokesperson said.

The Commission said it suspects that Meta does not comply

with DSA obligations related to addressing the dissemination of

deceptive advertisements, disinformation campaigns and

coordinated inauthentic behaviour in the EU.

It also singled out the non-availability of an effective

third-party realtime civic discourse and election-monitoring

tool ahead of the elections to the European Parliament.

The Commission also cited concerns about Meta's phasing out

of its disinformation tracking CrowdTangle without an adequate

replacement.

Meta has five working days to inform the EU about remedial

actions taken to address the concerns.