Dozens of Ukrainian officials have been sacked since Russia's invasion, as President Volodymyr Zelensky seeks to reassure Western allies sending wartime aid.

Yury Shchygol, head of the State Special Communications Service of Ukraine, and his deputy Victor Zhora were both dismissed on Monday, cabinet official Taras Melnychuk said.

He did not give a reason for the dismissals, but anti-corruption officials later said they were investigating the misappropriation of over $1.7 million worth of government funds during Shchygol's time in office.

From 2020 to 2022, "the owner of a group of companies, in collusion with the management of the State Special Communications Service of Ukraine, developed a scheme to misappropriate budget funds allocated for the purchase of hardware and software," Kyiv's anti-graft bureau said.

The group of companies, which investigators did not name, then claimed to buy software from a foreign manufacturer for 62 million hryvnias ($1.7 million) more than its actual value and pocketed the difference, it said.

Six people are currently listed as suspects in the case, it said.

Ukraine has been fighting an uphill battle against systemic corruption, one of the reforms required by the West for membership to institutions like the European Union.

Prosecutors announced earlier this month that two senior defence officials were suspects in a large-scale fraud case involving the purchase of military uniforms from a Turkish firm.