WARSAW, Feb 25 (Reuters) - Poland has relaunched talks with Lockheed Martin’s MEADS on a medium-range air- and missile-defence system, the deputy defence minister was quoted as saying in comments published on Thursday.

The tender, whose value defence officials estimate at around $5 billion, is central to Warsaw’s large-scale army modernisation programme, speeded up in response to the Ukraine crisis and Russia’s renewed assertiveness in the region.

Poland had previously excluded the U.S. Lockheed-led consortium from the tender, short-listing two contenders: a consortium of European group MBDA and France’s Thales SA , and U.S. firm Raytheon Co, as potential suppliers.

Last year, Poland’s former centre-right government announced it would purchase Raytheon’s Patriot system, a decision which the Law and Justice (PiS) party, then in opposition but now in government, said it would review should it come to power.

Speaking to Reuters shortly before the election, Bartosz Kownacki, who went on to become deputy defence minister in charge of army modernisation, said a PiS government would reconsider Lockheed’s offer as a cheaper option.

Following PiS’ decisive election victory in October, the conservatives challenged the deal, questioning the “original cost and timeline assumptions of Raytheon’s offer, as well as those regarding the scope of (U.S.) cooperation with Polish industry” - a reference to how many of the jobs involved might go to Poles, and to potential technology sharing.

“We’re relaunching talks with MEADS,” daily Dziennik Gazeta Prawna quoted Kownacki as saying in a report published on Thursday.

“We’re still discussing who will be the supplier of the missile defence ... solution. Various options and various suppliers are possible. It all depends on the conditions which will be offered to us,” Kownacki said.

MEADS’s offer to Poland still stood, the daily quoted the company as saying.

Earlier this month, Kownacki said that Raytheon’s Patriot remained Poland’s first choice in the tender, but only if the price was lowered and Poland could access certain U.S. defence technologies. (Reporting by Wiktor Szary; Editing by Ruth Pitchford)