Ukraine
“We will plan for this year, and next year, and the year after and beyond," the defence secretary said.
Vita Hannych is one of many Ukrainian noncombatants being held by Russian forces for months following their invasion.
"As long as Russia sits on Crimea, Ukraine will never be safe."
The current age limit is 27.
Britain wants to "intensify" its support for Kyiv.
The battle for the small salt-mining town in the Donbas region of Ukraine has been one of the bloodiest of the entire war.
Valery Gerasimov has replaced General Sergei Surovikin as the man in charge of the invasion.
Meanwhile, the UK believes Moscow is "prioritising avoiding reputational damage".
It would have been the first major truce 11 months after Russia's invasion.
It comes after Moscow tried to blame a recent failure on low-level Russian soldiers.