The European Union will act as a key partner of the G7 in matters of ensuring the security and economic development of Ukraine, European Commission President Ursula von der Leyen has said.

"Today, we are committing to Ukraine's long term security and economic prosperity within the Euro-Atlantic community. The G7 will issue today a declaration to this effect. The EU will be a key partner in this endeavour," von der Leyen said in a statement tweeted by the European Commission on Wednesday.

She said the EU and its G7 partners have stood shoulder to shoulder with Ukraine since day one of the invasion, provided humanitarian support, financial assistance, as well as weapons and training.

"We will continue to support Ukraine's economic endurance so it can stand up to Russia's aggression. We will continue to impose costs on Russia through sanctions. We will continue to hold Russia accountable for its war crimes. And we will continue, through Ukraine's accession path, to support its admirable reform efforts," von der Leyen said.