Correction: This story has been changed to reflect that Norway expects the program to replace its fleet to take more than 10 years.

LONDON — Norway has narrowed the search for a contractor to build a new fleet of submarines down to DCNS of France and Germany's ThyssenKrupp Marine Systems (TKMS), the Ministry of Defence (MoD) said.

"DCNS and TKMS are the largest manufacturers of submarines in Western Europe. They have extensive experience in building advanced submarines and a large industrial capacity. The submarines offered by these two companies will be a good starting point for Norway's future submarines," the MoD said in an April 7 statement.

Norway has been investigating the options to replace its six Ula-class boats for the last two years. The MoD said that based on economic, industrial and military assessments, the French and German yards were the strongest candidates should a decision be taken to go ahead with the purchase.

Both companies have a decades-long track record of supplying systems to the Norwegian Navy.

Several other submarine yards were vying to be shortlisted, most notably Saab's Kockums location in neighboring Sweden.

In parallel to the shipyard selection, Oslo is negotiating a cooperation deal with several other nonsubmarine-building nations to see if a joint procurement is possible.

Those talks, primarily with the Netherlands and Poland, will continue, according to the MoD.

Norwegian defense officials earlier this week played down remarks from the head of the Polish MoD's Armament Inspectorate that Warsaw was in advanced talks for a cooperation deal.

The officials said Oslo hadn't decided whether go forward with a deal and with whom.

The Polish Navy is looking to replace it's three-strong fleet of Kobben-class submarines.

The MoD said recommendations on a new submarine would be presented to the government later this year ahead of a formal procurement program being presented to the Norwegian Parliament for approval.

"We have yet to make a decision to go ahead with a procurement program, nor have we made a decision regarding a final supplier. Significant work remains before a procurement program can be presented to the Norwegian Parliament," the MoD said.

Norwegian officials told Defense News earlier this week that no decision had been taken on whether all six Ula-class boats would be replaced.

Under current plans, Norway intends to operate the current fleet until the mid-2020s. The program to replace the boats is expected to take more than 10 years, with the first delivery around seven years after contract signing. The subsequent delivery schedule is planned to be one submarine per year.

Oslo has already laid down tough offset requirements for the successful bidder saying the procurement will be used to help ensure the continued development of a competent and competitive local defense industry.

"The Norwegian Parliament expects that a potential future procurement will ensure contracts for the Norwegian defense industry equal to the procurement cost, and that these contracts will provide access to the home market of the chosen supplier," the MoD said.

DCNS said it was offering its Scorpene submarine. Thyssen Krupp had no immediate commentdid not comment by press time.