Tata Steel's Dutch employees throw spanner in Thyssenkrupp JV works

* Dutch works council started evaluation on May 1

* Expect to need at least 2-3 months - president

* Thyssenkrupp (IOB: 0O1C.IL - news) , Tata Steel (BSE: TATASTEEL.BO - news) plan signing by end-June (Adds more detail on works council's demands and JV deal)

By Bart H. Meijer

AMSTERDAM, May 18 (Reuters) - Tata Steel's Dutch works council has called into question a timeframe for completing a joint venture between the Indian group and Thyssenkrupp by end-June, saying it may need more time to assess the deal, its president said.

"We expect to need at least two to three months to finish our process," Dutch works council president Frits van Wieringen told Reuters on Friday. The council started its evaluation on May 1.

Tata's Dutch works council last month said it still had "major reservations" over the consequences of the joint venture for the Dutch activities and its staff, even though Tata promised limited job losses and an independent position for the Dutch operations within the new company.

"Thyssenkrupp is the only party commenting on the expected end date," van Wieringen said.

Thyssenkrupp earlier this week said it expected to be able to sign the deal with Tata Steel, agreed in principle in September, in the first half of the year. Tata Steel confirmed http://www.tatasteel.com/media/6829/tata-steel-outcome.pdf that timeline a day later.

But this will not happen without the consent of the Dutch workers, van Wieringen said.

The planned transaction would combine Thyssenkrupp's and Tata Steel's European steel operations to create the continent's second-largest steelmaker after ArcelorMittal (LSE: 0NSF.L - news) with sales of 15 billion euros ($17.7 billion).

The council said it would scrutinise the deal very critically, as it looked for guarantees on investment plans and research activities relating to the automotive and packaging steel activities to remain in the Netherlands.

"A thorough process is more important to us than speed," van Wieringen told Reuters. "We will not be pressured into a deal."

The groups had previously aimed to sign the deal to combine their European steel activities in the beginning of 2018, and had foreseen its closure at the end of the year.

But Tata Steel's board still needs the final consent of trade unions and the works council.

Tata Steel Netherlands reached a preliminary agreement with Dutch unions in March, after promising job losses would be limited to between 300 and 400 supporting functions while excluding any forced redundancies until 2026.

Tata also guaranteed its Dutch division it could continue to operate as an independent, fully integrated steel company within the joint venture, with control over its own profits and with an independent supervisory board.

Thyssenkrupp declined to comment. ($1 = 0.8491 euros) (Additional reporting by Christoph Steitz in Frankfurt and Tom Kaeckenhoff in Duesseldorf)