(AFP) - Foreign donors have pledged 60 billion euros ($66 billion) of new financial support for Ukraine, the UK said Thursday, as an international conference aimed at funding the war-ravaged country's reconstruction closed.

"We had not envisaged this to be a pledging conference. Nevertheless, today at this conference, we can announce a combined 60 billion euros in support to Ukraine," said James Cleverly, foreign minister of the UK, which hosted the meeting.

The commitments from governments and international organisations target supporting Ukraine in the short- and medium-term, Cleverly said at the closing session of the London conference.

"This provides us with the medium-term predictable support that will unlock the macro-economic stability that Ukraine needs," he said, adding that efforts were now focused on unlocking "the enormous potential of the private sector".

"Ukraine will rebuild, but they cannot do it alone, so together as governments as international organisations, as businesses, as representatives of civil society, we have shown Ukraine and the Ukrainian people that we stand with them," he added.

Ukrainian Prime Minister Denys Shmygal told delegates that "we are starting to rebuild Ukraine this year, we are not waiting for the end of the war" as he thanked them for their financial backing.

"We are much closer to fully mobilising the $14.1 billion we need," he added, referring to a World Bank estimate of what is urgently required.

- 'Much closer' -

In the medium-term, more than $400 billion will be needed to rejuvenate the Ukrainian economy, according to estimates.

Shmygal also welcomed the commitment of "almost all" of those present in supporting the idea that Russia "must pay for its crimes and the destruction it has caused in Ukraine".

"We need to finalise a compensation mechanism that will allow frozen Russian assets to be used to rebuild Ukraine," he urged, with international efforts currently mired in legal discussions.

One of the conference's main goals was to involve the private sector by putting in place mechanisms to guarantee investments in Ukraine, where the army is currently in the midst of a counter-offensive against Russian forces.

Nearly 500 companies from 42 countries including big names like Google, Siemens, Vodafone, Hitachi, Virgin Group and Rolls-Royce have pledged to play their part, Cleverly said.

The bulk of the 60 billion euros comes from a 50-billion-euro aid package that the European Union plans to roll out until 2027, and which was announced on the eve of the conference.

The United States also announced $1.3 billion in aid, targeting the energy and infrastructure sectors in particular.

Ukrainian President Volodymyr Zelensky addressed the conference remotely on Wednesday, telling Western leaders that "the eyes of the world are looking at us and whether we will defeat Russian aggression".

"Also, the world is watching to see if we will restore normal life in such a way that our transformation will land an ideological defeat on the aggressor," he added.

In recent days, Ukrainian forces have claimed limited gains in a highly touted counter-offensive to win back territory that Russia captured after launching its full-scale offensive in February last year.

Overnight, they struck a bridge that connects southern Ukraine to the annexed Crimean peninsula, according to a Russian official.

"During the night a strike hit the Chongar bridge. There are no victims," Sergei Aksyonov, the Russia-installed governor of Crimea, said on Telegram.

Germany will host the Ukraine Recovery Conference in 2024.

© Agence France-Presse