Operation Orbital, the United Kingdom’s security training mission to Ukraine, has been extended by three years, Defense Secretary Ben Wallace said following meetings with his Ukrainian counterpart Andriy Zagorodniuk in Kiev.

“My recent visit to the Donbas region made clear not only the costs inflicted by Russian-backed separatists, but also the resolve the Ukrainian Armed Forces have demonstrated in defending their territorial integrity,” Wallace said on Monday, November 4.

“That is why we are extending our training mission to Ukraine for another three years – so we may train thousands more Ukrainian personnel and continue to make a difference.”

The mission to Ukraine will be extended until March 2023, according to the U.K.’s defense ministry.

More than 1,300 U.K. military personnel have deployed to Ukraine and trained more than 17,500 members of the country’s armed forces since the mission began in 2015 following Russia’s annexation of Crimea the year prior.

The U.K. expanded Operation Orbital last year, deploying units of the Royal Navy and Royal Marines after Russia’s seizure of three Ukrainian ships in the Sea of Azov in November 2018. The HMS Duncan, a Royal Navy destroyer, took part in a multinational naval exercise near Odessa in July.

Earlier this year, Canada extended its security force training mission in Ukraine until March 2022.

In 2016, NATO established the Comprehensive Assistance Package for Ukraine, which includes a variety of internationally-led initiatives to improve Ukraine’s security capabilities.

Germany, Poland, Romania, Czech Republic, Lithuania, Bulgaria, the Netherlands and the United States are among the NATO members that have contributed to developing Ukraine’s command and control, cyber and hybrid-warfare defense, medical and communications training and political reforms involving the defense sector.

More than 10,000 people have been killed since an insurgency broke out Eastern Ukraine in April 2014 following Russia’s annexation of Crimea.