Russian opposition leader Alexey Navalny is continuing his hunger strike in a prison hospital where he hasn’t been allowed to see his own doctors, one of his lawyers said Tuesday.

In an Instagram post released on Tuesday, Navalny thanks his supporters and joked that he looks like “a skeleton” who could be used to scare children into finishing their food. “It was pretty bad over the weekend,” he wrote, citing the searches and transit he endured when being moved to the prison hospital.

“After Novichok, potassium isn’t scary either”, - he wrote, referring to the nerve agent used in the poisoning attempt on him in August that he and western governments blame on the Kremlin.

Navalny, the most prominent opponent of President Vladimir Putin, returned to Russia in January after nearly four months of treatment in Germany following the poison attack. He was jailed on arrival for breaking the terms of a suspended sentence given for an earlier criminal conviction. The Kremlin denies he was poisoned and says his case isn’t political.