The 27-nation bloc set up a programme for Ukrainian forces in November with the initial target of training 15,000.

"This will be reached probably before the end of the second quarter of this year and there will be a new additional target of a further 15,000 Ukrainian soldiers trained by various European countries," an EU official said.

"So that will bring the number of Ukrainian soldiers trained in this scheme to 30,000."

The increased figure -- to be formally announced at an EU-Ukraine summit in Kyiv on Friday -- comes as European allies step up their military support.

Several EU nations have pledged to provide German-made Leopard 2 tanks to Kyiv and are already training Ukrainian troops to use them.

It is unclear if that training is covered by the EU programme.

The EU training is being carried out across multiple European countries, with its headquarters in Ukraine's neighbour Poland.

Members states have also separately trained Kyiv's forces to use the weapons systems they are supplying.

The United States, Britain and other international backers of Ukraine have in addition trained thousands of troops.

Ukraine has pleaded with it allies to help bolster its forces ahead of a feared broader Russian offensive in the spring, and to allow its troops to go on the attack instead.

Grinding battles over the winter in the east of the country focused around the town of Bakhmut has taken a heavy toll on both sides.