Advances in Kupyansk, which Russia claimed to have captured in November, mark one of Ukraine’s major successes on the battlefield over the last two years, as Ukraine’s President Volodymyr Zelenskyy ...

Huge questions hang over the idea, from security to logistics, given the fierce fighting on the front lines and the daily Russian aerial assaults on Ukraine’s cities.

The issue of ceding territory remains a major sticking point in negotiations, and Vladimir Putin last week reiterated his ...