Reuters-- Prime Minister Haider al-Abadi declared final victory over ISIS on Saturday after Iraqi forces drove its last remnants from the country, three years after the militant group captured about a third of Iraq's territory.

Iraqi forces recaptured the last areas still under ISIS control along the border with Syria and secured the western desert, Abadi said, thus marking the end of the war against the militants.

His announcement comes two days after the Russian military announced the defeat of the militants in neighbouring Syria, where Moscow is backing Syrian government forces.

Abadi declared Dec. 10 an annual national holiday.

The parade was not being broadcast live and only state media was allowed to attend, but several squadrons of Iraqi helicopters flew over Baghdad on Saturday carrying Iraqi flags in an rehearsal for the victory parade.

Fighter jets were seen and heard flying over Baghdad's skies on Sunday.