US Secretary of State Antony Blinken has said the United States would provide more than $1.3 billion (€1.19bn) in additional aid to Ukraine to help the country recover and rebuild its energy grid.
"We will provide more than $1.3 billion in additional aid to help Ukraine," Mr Blinken told the Ukraine Recovery Conference in London.
"We're going to invest $520 million to help Ukraine overhaul its energy grid."
"As Russia continues to destroy, we are here to help Ukraine rebuild - rebuild lives, rebuild its country, rebuild its future," Mr Blinken said.
"Let's be clear - Russia is causing Ukraine's destruction, and Russia will eventually bear the cost of Ukraine's reconstruction," he said to applause, echoing remarks by leaders from Britain and the European Union.
The new funding - which comes from money already approved by the US Congress - is in addition to $63bn provided by the United States to Ukraine since Russia invaded in February 2022.
Some $40bn of the assistance has come in weapons and other security support.
Opening the conference, British Prime Minister Rishi Sunak said: "Before this terrible war, Ukraine's economy was becoming a huge investment opportunity."
Mr Sunak promised to keep tough sanctions in place "until Russia pays up", and use seized assets to get Ukraine back on its feet.
Thousands of delegates from business, government and civil society groups have gathered for the conference, which Mr Sunak hailed as an opportunity to "plant the seeds of Ukraine's future".
It is the second conference to be held since the Russian invasion in February last year.
It came as he announced €2.7billion in bank loan guarantees to bolster the rebuilding of Kyiv, in partnership with the World Bank.
He said Ukraine represents an investment opportunity, with its resistance to the Russian invasion demonstrating its people's capacity for innovation.
Speaking at the conference via video-link, Ukrainian President Volodymyr Zelensky called for "agreements" to be transformed into "real projects" to support his country's recovery.
He thanked "every country where we have agreed on principles for recovery" and said: "We must move from region to agreements and from agreements to real projects."
Mr Zelensky, who is pushing for Ukraine to join NATO and the European Union, urged Western leaders to have the "courage" to acknowledge that his country is already a key part of their economic and defence alliances.
"We are only waiting for the courage of the alliance leaders to recognise this reality, politically."
Addressing the conference, European Commission President Ursula von der Leyen said she had "no doubt" that Ukraine would join the EU.
She praised the progress and speed of reform in the country. "We can never match their sacrifice, but we can, and we do stand united," she said.
Ms von der Leyen, setting out her hopes for the future of Ukraine, said it would become a "country that attracts foreign investment, a country that is master of its future, a country that is a member of the European Union".
"Together we gather here to tell Ukrainians that their dream is also our dream," she remarked.
She said that the EU had a "special responsibility" towards Ukraine in the long term as she outlined investment plans for the country.
"Ukrainians tell us, when they imagine their future, they see Europe's flag flying over their cities. I have no doubt that Ukraine will be part of our union."
Tánaiste Micheál Martin said Ireland will pay its share of the €50 billion being pledged by the EU for reconstruction in Ukraine.
Mr Martin who attended the conference also repeated Ireland's support for Ukraine's accession to the EU.
He also held bilateral meetings including with the UK and Japanese governments.
Mr Martin told the conference that Ireland has provided 185 million euro in bilateral assistance to Ukraine since 2022.
It is also hosting 90,000 Ukrainians displaced by this war which represents 1.8% of the population.
He said: "Time and time again, we have been inspired by the tremendous resilience shown by the people of Ukraine. That same determination and resolve will be needed to rebuild their country, with support from international partners, including Ireland."
EU adds €3.5bn to Ukraine weapons fund
The European Union has agreed to add €3.5bn to a fund used to pay for weapons for Ukraine, as the bloc looks to keep up support for Kyiv.
Sweden, which holds the EU's rotating presidency, said the green light had been given to bolster the European Peace Facility at a meeting in Brussels.
The EU's 27 countries have already used around €5.5bn of the joint fund - set up in 2021 to support partner countries around the globe - to help arm Ukraine.
That includes €3.6bn to reimburse EU member states for weapons they supply to Ukraine and €2bn dedicated to a programme to send ammunition to Kyiv.
EU leaders already topped up the fund, which is meant to run to 2027, by €2bn late last year and gave their agreement in principle for adding the latest €3.5bn.
Some EU nations have pushed to raise the limit to ensure that there is enough money to keep aiding militaries in partner countries in Africa and other regions.
Overall, Brussels says that some €15bn have been provided by EU member states and the bloc's joint fund to arm Ukraine since Russia's all-out invasion.
The EU is also training thousands of Ukrainian troops and announced in February that 30,000 soldiers should be trained by the end of this year.
