Ukraine's President Volodymyr Zelensky has ruled out giving up any of his country's territory in a potential peace deal with Russia.

In a BBC interview to mark a year since Russia's full-scale invasion, he warned conceding land would mean Russia could "keep coming back", while Western weapons would bring peace closer.

Mr Zelensky also said a predicted spring offensive had already begun.

"Russian attacks are already happening from several directions," he said.

He does, however, believe Ukraine's forces can keep resisting Russia's advance until they are able to launch a counter-offensive - although he repeated his calls for more military aid from the West.

"Of course, modern weapons speed up peace. Weapons are the only language Russia understands," Mr Zelensky told the BBC.

He met UK and EU leaders last week in a bid to bolster international support and to ask for modern arms to defend his country. When Ukraine's president asked for modern fighter jets, UK Prime Minister Rishi Sunak said "nothing is off the table".

But Kyiv has become increasingly frustrated with the speed with which Western weapons have arrived. Deliveries of battle tanks - promised last month by a swathe of Western countries, including Germany, the US and the UK - are still thought to be weeks away from arriving on the battlefield.

President Zelensky also addressed a threat by Belarus leader Alexander Lukashenko to wage war alongside Russian troops from his territory if a single Ukrainian soldier crossed the border.

"I hope [Belarus] won't join [the war]," he said. "If it does, we will fight and we will survive." Allowing Russia to use Belarus as a staging post for an attack again would be a "huge mistake", he added.

Russian forces launched part of their full-scale invasion from Belarus 12 months ago. They drove south towards Ukraine's capital Kyiv but were fought back and made to retreat within weeks, after suffering heavy casualties.

When asked if he was surprised by Russia's tactics in the war, Mr Zelensky described them as "valueless".

"The way they destroyed everything. If their soldiers received [and carried out] those orders, that means they share those same values."

Ukrainian data released this week suggested Russian troops in Ukraine were dying in greater numbers this month than at any time since the first week of their invasion. The figures cannot be verified, but the UK's Ministry of Defence said the trends were "likely accurate".

"Today, our survival is our unity," said Mr Zelensky on how he thought the war will end. "I believe Ukraine is fighting for its survival." His country was moving towards Europe economically, as well as through its values, he said.

"We chose this path. We want security guarantees. Any territorial compromises would make us weaker as a state."

"It's not about compromise itself," he said. "Why would we be afraid of that? We have millions of compromises in life every day.

"The question is with whom? With Putin? No. Because there's no trust. Dialogue with him? No. Because there's no trust."