There has already been over a month of bloodshed. But the push for a diplomatic solution to Russia's invasion of Ukraine appears to be making tangible progress.

Delegates from both sides sat down on Tuesday in Istanbul.

It was their fourth round of talks, and Ukrainian officials say they have paved the way for a bilateral summit.

They say both sides discussed a new framework to ensure Ukraine's security without NATO membership.
They say Ukraine would not host foreign troops under such a scenario.

The officials even went so far as to name possible security guarantors -- including Israel, Poland, Canada and Turkey.

Russia's chief negotiator describes the talks as constructive. He says they narrowed their differences somewhat in terms of military and political issues.
He says his team will examine proposals and report to President Vladimir Putin. The delegate says a summit would first require a deal among the two country's foreign ministers.

Another Russian delegate says his country has decided to drastically scale down military operations around Kyiv and the northern city of Chernihiv to create conditions for more dialogue.

It comes after weeks of merciless shelling across Ukraine -- especially in Mariupol, a strategic port city in the southeast. Russia still aims to take full control of the area.

The mayor's office told local media 5,000 people have been killed, including more than 200 children.

Elsewhere, concerns are rising about the Institute of Physics and Technology in Kharkiv. Russian troops have once again attacked the facility, which handles nuclear material. Authorities are reporting serious damage. They say the actual extent is unknown due to fierce fighting.

The Ukrainians are not rolling over. They are said to have retaken control of Trostyanets -- a town in the northeastern region of Sumy.

Ukrainian officials say they have also retaken key areas around the capital Kyiv.