The Wall Street Journal reported last week that Sega Sammy was nearing a deal to buy the Finnish firm behind the mobile game Angry Birds for about $1 billion. Rovio has said it was in talks with Sega Sammy over a possible tender offer.

"No formal decision has been made in this regard at this time, while it is true that we are considering such strategic option," Sega Sammy said in a statement.

The matter will be discussed during a board of directors meeting on Monday, added Sega Sammy, which offers the iconic action game series "Sonic the Hedgehog".

Sega Sammy shares fell 4.3% by midday in a broader market that was virtually unchanged.

"Sega Sammy's mobile gaming business is centred on the domestic market, while 'Angry Birds' is well known overseas. The acquisition would make it easier for Sega Sammy to grow globally," Toyo Securities analyst Hideki Yasuda said.

"But there has been no big hit (from Rovio) other than Angry Birds, which was originally launched more than 10 years ago. The news would have been welcomed more positively if investors had seen newer technologies or more growth potentials," Yasuda said.

Rovio received a 683 million euro ($750 million) takeover bid in January from Israeli peer Playtika Holding Corp, but the talks were called off last month.

($1 = 0.9112 euros)

(Reporting by Kiyoshi Takenaka; Editing by Himani Sarkar)