Contact with the Ukrainian troops, who asked Russian border guards to open a humanitarian corridor and found themselves on Russian territory, is being maintained through diplomatic channels, according to the Ukrainian National Security and Defense Council (NSDC).

"A representative of the Ukrainian Foreign Ministry is working with them, talks over their repatriation are underway," NSDC information and analytical center spokesman Andriy Lysenko said at a Monday briefing, without giving the exact number of the troops currently on Russian territory.

A field camp has been set up for the Ukrainian troops not far from the Gukovo border checkpoint, spokesman for the Rostov regional office of the Federal Security Service (FSB) Border Guard Service Vasily Malayev told Interfax earlier on Monday.

"Currently, there are 438 people in the field camp that was additionally set up specifically for the Ukrainian troops," Malayev said.

The Ukrainian troops had a shower, changed into clean clothes and had meals, he said.

Malayev said earlier that in the early hours of August 4 over 430 Ukrainian troops asked Russian border guards to open a humanitarian corridor through Russia. They are expected to be handed over to the Ukrainian side at the Matveyev Kurgan checkpoint.