"I would like to announce that I am in talks with my British colleague Ben Emmerson on a joint complaint to the ECHR on Savchenko's case," the lawyer wrote on Twitter.

Read alsoSavchenko to be swapped for Russian GRU officers by late May – mediaHe added that another Savchenko's lawyer Nikolay Polozov would visit her in the detention center in the coming days.

"We have already agreed. He will finish something that he did not manage to do. So, we'll wait," Feygin said.