Google could be wading into troubled waters again for antitrust over AdWords, as the European Union (EU) is reportedly considering taking action against the company.

The EU watchdogs are apparently unhappy with Google's advertising services — including AdWords — claiming that it is in violation of competition rules.

The news comes courtesy of a Bloomberg report, which cites people who supposedly are in the know.

"The European Union is taking steps that could lead to a third antitrust complaint against Google, this time over its lucrative advertising services, according to three people familiar with the EU investigation," revealed the publication.

Reportedly, officials from the EU have asked for the critics' permission, so that the evidence can be shared with Google. The publication's sources, however, choose to remain anonymous as the matter is a private one. One of the sources, however, disclosed that one such permission request for evidence sharing with Google was sent as recently as last week.

EU's request for evidence sharing is usually a forerunner of a formal complaint or statement of objection, which catalogs how a company may have potentially violated antitrust laws in the EU.

While the sources did not reveal by when the EU would be leveling the charges against Google, in May, Margrethe Vestager, the competition commissioner, expressed optimism that her office would be able to come to a resolution on the AdWords issue, but "within a reasonable timeframe."

In the event the EU does take action against Google, this would be the third antitrust complaint against the Alphabet-owned company.

Google is currently embroiled in two more antitrust investigations with the EU, which were escalated post Vestager's appointment as the antitrust chief in 2014.

In 2015, Google came under the scanner for promoting its services over that of its rivals in an unfair manner in the context of search services for shopping. In April, it was charged with an official complaint pertaining to its Android OS, which it is required to answer by summer.

In the previous two antitrust cases, the commission has been swift in sending across the statement of objections post sending out requests to share evidence regarding the case. In the two older antitrust cases, Google has maintained that it is innocent.

The current complaint could adversely affect Google's revenue stream when compared to the older lawsuits, especially considering that AdWords is pivotal in boosting the company's advertising sales.

Both the Commission and Google are staying mum on the matter and have declined to comment.