CARACAS May 23 (Reuters) - Venezuelan state oil company PDVSA is preparing to issue $2.5 billion in promissory notes to settle unpaid bills to services companies, according to industry sources and documents seen by Reuters.

PDVSA has already issued at least $310 million in debt securities as part of a broader effort to prevent crucial oil services providers from downing their tools for lack of payment, Reuters reported this month.

The company has hired little-known, Miami-based financial services firm CP Capital to structure 3-year notes with a one-year grace period that will have the same status as PDVSA’s global bonds, according to documents obtained by Reuters.

The operation creates additional financial obligations for a company already facing doubts about its capacity to meet ballooning bond payments amid low oil prices, a collapsing socialist economy, and chronic shortages reminiscent of the Soviet bloc.

President Nicolas Maduro said any talk of default is part of an international campaign to undermine his government and points out that the ruling Socialist Party has never missed a bond payment.

“CP Capital has been hired to advise PDVSA on the exchange of commercial invoices for financial debt with a minimum amount of $2.5 billion,” read a PDVSA document seen by Reuters.

“PDVSA will issue unsecured debt with the same risk levels as PDVSA’s other publicly traded notes and obligations,” read the document, adding that CP Capital will work with providers to help them get paid for outstanding bills.

PDVSA’s board of directors approved the operation in April, according to a separate PDVSA memorandum.

Neither PDVSA nor CP Capital responded to requests for comment.

The document did not say which companies would participate.

PDVSA’s most recent financial statements show it owes nearly $21 billion to providers, though industry sources say the amount denominated in dollars is around $7 billion.

Participants in the operation include small and medium-sized service companies but not top industry players, according to two industry sources involved in the negotiations.

One supplier has agreed to the proposal because it has not received hard currency payment in over a year, according to documents provided by a company source who asked that the company not be named.

That company was told by PDVSA that the securities had a “cross default” clause linking them to PDVSA’s other bonds, according to the documents.

Many providers have said they will not participate in the operation due to the heavy discounts they will likely suffer, according to a third industry source also involved.

The sources asked not to be identified because talks are ongoing and because they are not authorized to comment publicly on the issue.

The total haircut to providers will depend on the market value of the promissory notes, which are expected to price below PDVSA’s bonds because they are more difficult to trade.

PDVSA’s benchmark 2022 bond trades at around 45 cents on the dollar. (Additional reporting by Marianna Parraga in Houston; Writing by Brian Ellsworth; Editing by Andrew Cawthorne and Andrew Hay)