FRANKFURT/BERLIN (Reuters) - Activist hedge fund Elliott said on Thursday it would step up pressure on Thyssenkrupp's TKAG.DE leadership to revive the German industrial conglomerate's fortunes, confirming it had taken a stake of less than 3 percent.

FILE PHOTO: The logo of German steel-to-elevators group ThyssenKrupp AG is pictured during the company's annual news conference in Essen, Germany, November 24, 2016. REUTERS/Wolfgang Rattay/File Photo

The stake increases the influence of interventionist investors on the group, which already counts Sweden’s Cevian as its second-largest shareholder. Cevian has called for a broad strategic review of the sprawling elevators-to-submarines group.

“Elliott believes Thyssenkrupp has significant scope for operational improvement which would benefit all stakeholders,” Elliott said in a brief statement, adding it would soon seek to start a constructive dialogue with the group’s boards.

Those talks will reveal Elliott's desire for far-reaching changes at the conglomerate, whose shares have fallen more than a fifth since CEO Heinrich Hiesinger took the job in 2011. The STOXX Europe 600 Industrial Goods & Services Index .SXNP has risen more than two thirds over the same period.

Investors have become more vocal in criticizing management for being too slow in selling a legacy steel business into a joint venture with Tata Steel TISC.NS, a move aimed at revealing the value of Thyssenkrupp's higher-tech businesses.

Elliott did not disclose the exact size of its stake, only saying that, as of Thursday, it did not exceed any thresholds forcing it to reveal it. Under German capital market rules, the first such threshold is 3 percent.

The move puts Hiesinger under pressure to launch a more radical overhaul, which some shareholders have suggested might be difficult to deliver under the existing management, or break up the firm, an idea he has resisted in the past with the backing of Supervisory Board Chairman Ulrich Lehner.

The chief executive is due to outline refinements to his existing strategy in a few weeks.

Thyssenkrupp declined to comment.

Shares in Thyssenkrupp traded 1.6 percent higher at 0849 GMT. They had posted their biggest single-day gain in almost a decade earlier this week when news about Elliott’s stake first emerged.

The investment is also in line with a pickup in the U.S. hedge fund’s activity in Europe this year, with sources saying Elliott sees a chance in a region where activist funds are usually less present.

A day earlier, Elliott, led by Paul Singer, raised its stake in German energy group Uniper UN01.DE to 8.03 percent, ahead of a shareholder meeting where it is trying to appoint a special auditor to investigate management.