US Vice-President Kamala Harris has pledged a $1.5bn (£1.18bn) package of aid to Ukraine, mostly for the country’s energy sector.

The funding, announced at a Ukraine peace summit in Switzerland, will help repair infrastructure damaged by Russian bombardments.

Ukrainian President Volodymyr Zelensky said on Tuesday that half of the country’s power-producing capacity had been destroyed in the war.

He has called on Western countries to provide more air defences to protect both energy infrastructure and urban population centres, and some have responded.

Russian attacks on the power grid have forced energy companies to institute rolling blackouts.

The package, from USAID and the State Department, includes $500m of new money for energy assistance and $324m redirected for emergency energy needs, a White House statement said.

“These efforts will help Ukraine respond to Russia’s latest attacks on Ukraine energy infrastructure by supporting repair and recovery, improving Ukraine’s resilience to energy supply disruptions, and laying the groundwork to repair and expand Ukraine’s energy system,” it added.

Another $369m has been pledged as humanitarian assistance to help displaced persons and communities affected by the conflict, and there are plans to send a further $300m to provide life-saving equipment for border guards and law enforcement.

Since the start of the war, the US has spent more than $3.2m on humanitarian aid for Ukraine, and nearly $1.5bn on the energy sector, the statement added.

Ms Harris is attending the summit in the Swiss mountain resort of Burgenstock, which aims to discuss basic principles for ending the conflict in Ukraine, in the absence of President Joe Biden.

But with Russia not invited and key players like China staying away, expectations for significant progress at the summit are low.