Armenia suffered casualties and lost two combat positions during clashes with Azerbaijan's forces, Russia's TASS news agency reported Tuesday, citing the Armenian defense minister.

"There are fatalities and wounded among Armenian troops as a result of fighting that erupted following an attack by Azerbaijani forces," Armenia's defense ministry said, adding that the number of casualties was being verified and that Yerevan had "lost control of two military positions".

Meanwhile, Azerbaijan's Defense Ministry said it had suppressed an Armenian counter-attack.

Armenia on Tuesday asked Russia to help defend its territorial sovereignty against Azerbaijan and said a heavy border clash between Azeri and Armenian forces was underway, TASS reported earlier.

(With input from Reuters, AFP)