Jan 4 (Reuters) - Venezuela's state-run oil company

PDVSA is asking some joint ventures to cut back crude production

amid an export paralysis, three sources close to the decision

said on Sunday, adding pressure to an interim government trying

to hang on to power.

The moves ‌include shutting down oilfields or well clusters

as stocks stored onshore mount and the company runs out of

diluents to ​blend Venezuela's heavy crude for shipment.

Caracas is in political crisis under an interim

government after ‍President Nicolas Maduro and his wife were

extracted by U.S. forces ⁠on Saturday. The OPEC ⁠country's oil

exports, its main source of revenue, have been at a standstill

following a U.S. blockade on tankers under ‌sanctions and the

seizure of two oil cargoes ​last month.

Chevron's ( CVX ) cargoes bound for the U.S. had been an

exception, continuing to move, because the company has a license

from Washington for its operations. ⁠But since Thursday, even

those have stopped, shipping ‍data showed ​on Sunday.

As part of his announcement of Maduro's detention and a

transition overseen by the U.S., President Donald Trump said on

Saturday that an "oil embargo" on the ‍country was in full force.

PDVSA's request to reduce oil production was made to

joint ventures including China National Petroleum Corporation's

(CNPC) Petrolera Sinovensa, Chevron's ( CVX ) Petropiar and Petroboscan

and Petromonagas, the sources said. Petromangas, previously

operated by PDVSA and Russian state-run Roszarubezhneft, is

being run solely by PDVSA.

PDVSA and CNPC did not immediately reply to requests for

comment. Chevron ( CVX ) said on Sunday ​it continues ‍to operate "in full

compliance with all relevant laws and regulations," without

providing details.

Workers at Sinovensa on Sunday were preparing to

disconnect up to 10 well clusters, one ​of the sources said, due

to a PDVSA request after an over-accumulation of extra heavy

crude and diluents shortage. However, the wells could be

quickly reconnected in the future, the person added.

On its side, Chevron ( CVX ) has not cut product output yet as

it has some room to keep storing, particularly at Petropiar, and

tankers have not stopped loading. However, its vessels have not

left the country's waters in recent days ​and storage capacity is

limited at Petroboscan, which could ultimately lead to cuts,

another source said.

Venezuela's oil minister Delcy Rodriguez, who is now

Venezuela's interim president, said last month the country would

continue producing and exporting oil despite ‍the U.S. measures