The Guardian is reporting 8,000 sq km retaken.
“Zelenskiy said about 8,000 sq km (3,100 square miles) have been liberated so far, apparently all in the north-eastern region of Kharkiv. “Stabilisation measures” had been completed in about half of that territory, Zelenskiy said, “and across a liberated area of about the same size, stabilisation measures are still ongoing”. Ukraine now has set its sights on freeing all territory occupied by invading Russian forces.”
The BBC reporting.
“In a late evening address on Tuesday, Mr Zelensky said his forces were fortifying their hold over 8,000 sq km (3,088 sq miles) of retaken territory in the Kharkiv region.
Last Thursday, President Zelensky said Ukrainian forces had retaken 1,000 sq km. By Sunday, that stated figure had tripled to 3,000 sq km, before rising again to 6,000 sq km.”
Two days ago the BBC had a flat out confirmed 1/5 of Ukraine has been taken by the Russians.
And two days ago, per BBC, Zel said 6k.
Democracy Now and The Guardian said 1k.
6k also claimed by Zel per Zubu Brothers:
“Zelensky Says Ukraine Has Retaken 6,000 Square KM, But Army “Worried” About Defending It”