LONDON (Reuters) - Russia said oil flows through the Caspian Pipeline Consortium (CPC), a major route for supplying Kazakhstan and exporting to the global market, were reduced by 30-40% on Tuesday after a Ukrainian drone attack on a pumping station.

The attack, which caused no casualties, took place on the eve of talks between the U.S. and Russian officials on ending the war in Ukraine. Following the meeting, from which Kyiv was excluded, U.S. President Donald Trump's administration said it had agreed to hold more talks.

Russian Deputy Prime Minister Alexander Novak said on Tuesday volumes had dropped by approximately 30-40% compared with before the drone attack on a pumping station in southern Russia.

"As a result of the attack, energy equipment, a gas turbine unit, and a substation were damaged," he said on Russian television. CPC pumps crude from companies that include Chevron and Exxon Mobil.

He said repairs might take several months.

The Caspian pipeline, which ships more than 1% of daily global supply, stretches over 1,500 km (939 miles) and carries crude from Kazakhstan's vast Tengiz oilfield on the northeastern shores of the Caspian Sea as well as from Russian producers.

A cut of 30% in CPC shipments could amount to as much as 380,000 barrels per day, according to Reuters calculations.

As well as being the main route for Kazakhstan's oil exports, Kazakhstan relies on the CPC pipeline for most of its own crude supplies.

Transneft, Russia's state pipeline operator, said Kazakhstan would have to cut exports by 30% as it meets its own needs.

The CPC said in a statement the oil pipeline "continues to operate" and was pumping oil to awaiting tankers on the Black Sea, though at reduced levels, while bypassing the damaged station.

Chevron-led Tengizchevroil (TCO), operator of the Tengiz oilfield, said in a statement on Tuesday it was monitoring the situation.

However, it said "production and export of crude oil via the CPC pipeline remain uninterrupted".

Kazakhstan's energy ministry also said the country was supplying oil without restrictions.

It said in a statement the pipeline from Tengiz to the Black Sea port of Novorossiysk was operating "without the participation" of the Kropotkinskaya pumping station. It did not mention the drone attack.

At least seven drones packed with explosives and shrapnel attacked the Kropotkinskaya station on the CPC pipeline in Russia's Krasnodar region causing "serious damage", Transneft said.

The General Staff of the Ukrainian armed forces said that it had attacked Russian energy infrastructure, including the CPC pumping station and the nearby Ilsky oil refinery.

"The Defence Forces of Ukraine reserve the right to strike strategic facilities that support Russia’s armed aggression. Operations aimed at dismantling the energy infrastructure fuelling Russia’s illegal war will continue," it said.

Russia launched a large-scale attack overnight involving 176 drones in the regions of Kirovohrad, Kharkiv, Kyiv and Cherkasy, the Ukrainian military said on Tuesday.

Benchmark oil prices rose on Tuesday to trade above $75 a barrel.

Shareholders in the CPC include U.S. majors Chevron and Exxon Mobil, as well as the Russian state, Russian firm Lukoil, and Kazakh state company KazMunayGas.

(Editing by Christopher Cushing, Jason Neely and Barbara Lewis)