The European Union's latest sanctions against Russia have come into effect as the crisis in Ukraine continues.

The measures have halted loans for five state banks and restricted business with energy and arms companies.

The sanctions include restrictions on Russian oil companies Rosneft and Transneft, as well as the petroleum unit of Russia's state-run gas company Gazprom and gun-maker Kalashnikov.

The companies face restricted access to EU financial markets.

The latest measures also target dual-use technology that could be used for military purposes.

While a ceasefire had already been agreed in eastern Ukraine, the EU has passed the latest measures to maintain the pressure on Russia over its behaviour.

The US and EU have accused Moscow of aiding the rebels in eastern Ukraine, by providing arms and soldiers to assist the separatist insurgency against the government. Nato has said Russia still has around 1,000 well-armed troops in the east of the country.

Russia has said it is preparing a response to the sanctions, with one senior official saying that EU cars could be targeted.

More than 3,000 people have been killed since the crisis erupted in eastern Ukraine in mid-April, following Russia's annexation of the Crimea peninsula.

Meanwhile, the EU has extended the list of individuals subjected to travel bans and asset freezes, mostly to include rebel leaders and some Russian officials.

"They comprise persons involved in actions against Ukraine's territorial integrity, including the new leadership in Donbass, the government of Crimea as well as Russian decision-makers and oligarchs," said the EU Council in a statement.

"This brings the total of persons subject to sanctions to 119 while 23 entities remain under asset freeze in the EU," it said.