Ukrainian Prime Minister Denys Shmyhal said on Thursday he was certain Ukraine would receive the $6.5 billion it needs this year for its rapid reconstruction programs from pledges made at a conference in London.

Earlier, Britain, the United States, the European Union and others pledged billions of dollars in additional help for Ukraine, going some way to meeting Kyiv's demand for more capital and commitments to specific projects, not only to rebuild but to further develop Ukraine into a strong member of the West.

Speaking on the final day of the Ukraine recovery conference, Shmyhal said his government had yet to assess all the pledges but that "I'm sure that in the nearest time, after this conference ... we will collect all the needed money."

On Wednesday, he said he expected to secure almost $7 billion in aid, money needed to spur his government's rapid recovery program - which is firstly focused on rebuilding the energy sector, especially before another winter.

Shmyhal also said there had been many expressions of interest from the business community in getting involved in projects in Ukraine, particularly after Britain announced the London Conference Framework for War Risk Insurance, which could pave the way for derisking investment.

He said that as yet he could not put a figure on the amount of business investment.

Nearly 16 months of Russia's war on Ukraine has destroyed homes, hospitals and other critical infrastructure. Western nations are keen to maintain support for Kyiv, which faces years, possibly decades, of rebuilding.

The total bill will be huge, with Ukraine, the World Bank, the European Commission and the United Nations estimating in March that the cost was at $411 billion for the first year of the war.

Shmyhal said that figure only referred to the land currently under Ukrainian control.

"I think after the liberation of all the Ukrainian territories, this amount will be doubled," he said. "And we understand that this a project for dozens of years."