ISW: Ukraine Advances Near Zaporizhzhia and Slovyansk on Day 1,552; Russian Losses Reach ~1,357,900

On May 26, 2026 — Day 1,552 of Russia's full-scale invasion — the Institute for the Study of War (ISW) published its daily assessment noting that Ukrainian forces registered geolocated advances in western Zaporizhzhia Oblast and in the Slovyansk direction, continuing limited offensive pressure despite the ongoing massive Russian aerial campaign. Russia launched 65 attacks against Ukrainian positions across all front sectors. Fighting remained heaviest in the Pokrovsk sector. According to the Ukrainian MoD's daily losses bulletin, Russian cumulative losses reached approximately 1,357,900 personnel as of May 26, with approximately +960 losses recorded over the preceding 24 hours. Equipment losses continued to mount including +1,307 UAVs and +39 artillery systems on May 26. ISW also assessed that Russia and Belarus appear to be setting conditions to potentially justify launching drone strikes on Ukraine from Belarusian territory — a significant potential escalation not seen since the early days of the invasion. Norway pledged approximately $40–42 million to support Ukraine's energy sector rehabilitation on May 26.