Ukraine's allies have pledged to send more weapons to help it defend against a renewed Russian offensive.

The US and others vowed to send artillery, anti-tank and air defence aid to Kyiv during a 90-minute video call on Tuesday.

Ukraine says it needs the weapons to help defend itself as Russia launched a new campaign in the country's east.

Clashes there have marked what Ukraine leader Volodymyr Zelensky said was the start of the "battle for the Donbas".

The eastern Donbas - which comprises the Luhansk and Donetsk regions - is where Russia is concentrating its efforts.

According to Ukraine, Russian forces have been attacking Ukrainian positions along the entire 300-mile (480km) front line since Monday.

It was amid these renewed attacks that Western leaders met to discuss further military assistance for Ukraine.

Following the meeting, the US defence department said additional military aircraft and aircraft parts had been sent to Ukraine to increase their fleet size and repair others in Ukraine's arsenal that were damaged.

The US defence department added that the US had not provided aircraft to Kyiv itself, and did not provide details on which countries have provided the aircraft.

President Zelensky has been appealing to the US for Soviet-made air defence systems and fighter jets as an alternative to a no-fly zone over Ukraine.

Last month, the US refused a proposal by Poland to provide it with MiG-29 fighter jets, which it would then transfer to Ukraine.

President Joe Biden, speaking to reporters after the meeting between Western allies, added that the US is planning to provide a further military aid package to Ukraine of a similar size to the $800m (£615m) aid package he announced last week, according to US media.

He said Washington would also be sending Ukraine more artillery - heavy guns deployed in land warfare.

Other countries also pledged to help Ukraine with further military assistance during the meeting.

"They [Ukraine] need support with more artillery, that is what we will be giving them," said the UK Prime Minister Boris Johnson in parliament after the meeting.

In Berlin, Chancellor Olaf Scholz said Germany was providing finance to enable Ukraine to buy anti-tank weapons and ammunition from German arms manufacturers.

Meanwhile, the Czech Republic said it would repair Ukrainian tanks and armoured vehicles when they are damaged in combat.

Further economic sanctions against Russia was another topic on the agenda.

The arms pledges follow persistent calls from President Zelensky for allies to increase their weapons supplies to Kyiv.

"We need heavy artillery, armed vehicles, air defence systems and combat aircraft — anything to repel Russian forces and stop their war crimes," Mr Zelensky said on Twitter last week. "Nobody will stop Russia except Ukraine with heavy weapons".

Russia fiercely opposes such assistance.

"The United States and Western states under its control are doing everything to drag out the military operation for as long as possible," Russia's defence chief Sergei Shoigu said.

The leaders also discussed how to provide security guarantees to Ukraine after the war even if it is not a member of Nato, a French presidential advisor said.

Nato is a military alliance whose 30 members - including the US, UK and Germany - have agreed to come to one another's aid in the event of an armed attack against any one of them.

Since Ukraine is not a Nato member, the alliance isn't obliged to come to its defence.

Its members fear that involving themselves in direct armed confrontation could lead to an all-out conflict between Russia and the West.

Instead, Nato members have supplied Ukraine with millions of dollars worth of military aid since Russia launched the invasion.