Russian and Ukrainian delegates concluded their third set of direct talks in Istanbul “about 40 minutes” after they started, the Russian state news agency TASS reported Wednesday, citing a source.

Officials from Russia and Ukraine began a third round of talks in Istanbul, with potential prisoner swaps on the agenda but little expectation of progress on ending the full-scale war that’s in its fourth year.

The third round of direct talks between Ukraine and Russia has begun in Istanbul on July 23. The meeting began with one-on-one talks between National Security and Defense Council Secretary Rustem Umerov and Vladimir Medinsky,