Ukraine's President Volodymyr Zelensky is set to attend an EU summit in Brussels Thursday as the guest of honour where he will press allies to deliver fighter jets "as soon as possible" in the war against Russia.

The Ukrainian president started a surprise tour of Europe on Wednesday with visits to Britain and France, marking just his second venture abroad since the Russian invasion almost one year ago.

His attendance at the EU summit in Brussels will be "a signal of European solidarity," said German Chancellor Olaf Scholz, who met with Zelensky Wednesday in France.

The visit to France -- which appeared to have been squeezed in at the last minute -- saw Zelensky hold a late dinner meeting with Scholz and French President Emmanuel Macron. Before that, he was in London for a ceremony-filled day, meeting with King Charles III and addressing parliament.

Despite the contrast in formats, the Ukrainian president's demands were the same -- more weapons, especially fighter jets and longer-range missiles, and faster deliveries.

"The sooner Ukraine gets long-range heavy weaponry, the sooner our pilots get planes, the sooner this Russian aggression will end and we can return to peace in Europe," Zelensky said in Paris.

"There is very little time," he warned.

Macron pledged that France would help Ukraine to victory in fighting the Russian invasion and would press on with efforts to deliver arms.

France is "determined to help Ukraine to victory and the re-establishment of its legitimate rights," he said.

He added: "Ukraine can count on France, its European partners and its allies to win the war. Russia cannot and must not prevail."

Scholz said Germany and its partners had backed Ukraine "financially, with humanitarian aid and with weapons", adding: "We will continue to do so as long as necessary."

- 'Wings for freedom' -

As the one-year anniversary of Russia's invasion looms and Ukraine braces for a new Russian offensive in the east, Zelensky is pushing ever harder for friendly nations to send tanks, jets and missiles.

Britain said it would consider the proposal for combat aircraft in the "long term", although the United States and other NATO allies remain wary of getting more embroiled in the conflict for fear of provoking Russia.

Britain has offered to train Ukrainian fighter pilots on top of an existing programme that has already prepared 10,000 troops for battle.

Zelensky -- dressed in his usual green fatigues -- received waves of applause as he made a historic address to both the lower and upper houses of the British parliament, on what was only his second overseas trip since the war began after his trip to the US.

"I appeal to you and the world... for combat aircrafts for Ukraine, wings for freedom," he said.

Prime Minister Rishi Sunak's office said he had tasked the defence secretary with "investigating what jets we might be able to give but, to be clear, this is a long-term solution rather than a short-term capability."

Speaking alongside Zelensky in front of a British tank, Sunak said that "nothing is off the table" for Ukraine -- including fighter-combat aircraft.

"Of course they are part of the conversation," he said but held back from giving a concrete commitment to provide fighter planes.

Zelensky said that fighter jets had been discussed and reiterated his call for longer-range missiles.

Russia subsequently said there would be a "response" from Moscow should Britain supply aircraft to Ukraine.

- 'He has changed' -

Zelensky has on occasion shown impatience with Macron, who held frequent telephone talks with Russian President Vladimir Putin even after the invasion and had expressed concern that Moscow should not be humiliated in any final settlement.

But Macron has now indicated France wants to support Ukraine until it emerges victorious in the conflict and announced it would send light tanks in a move that prompted Germany to follow suit with battle tanks.

"I believe he has changed," said Zelensky in an interview with the Le Figaro daily published ahead of the talks.

"And that he changed for real this time. After all, he (Macron) opened the door to tank deliveries."

Moscow said Tuesday that Russian forces were advancing towards Bakhmut and Vugledar -- two key centres of fighting in the eastern Donetsk region of Ukraine, now the flashpoint of the war.

On Tuesday, Denmark, Germany and the Netherlands promised that Ukraine would get at least 100 tanks in the coming months, as the German defence minister visited Kyiv.

Germany recently gave the green light for Leopard battle tanks to be sent to Ukraine after a tireless campaign by Zelensky and allied countries.

Germany's defence minister said Berlin hoped to deliver the first tank battalion by April.

Putin, however, remains defiant.

Updated maps of Russia have gone on sale in Moscow bookstores that include four annexed Ukrainian regions: Zaporizhzhia, Kherson, Lugansk and Donetsk. Putin regularly refers to them as "our historical lands".