(Adds Maduro quotes, context)
CARACAS, Sept 8 (Reuters) - President Nicolas Maduro has invited bondholders to unspecified "negotiations" over Venezuela's foreign debt in coming days in response to recent U.S. financial sanctions.
The government and its state oil company PDVSA have to pay about $4 billion in debt maturities and interest during the rest of 2017 as the country's currency reserves have fallen.
"All bondholders are invited to various rounds of negotiations over the next few weeks," Maduro said in a speech late on Thursday to the new Constituent Assembly.
Maduro reiterated that Venezuela would keep honoring its debt, but said he wanted to talk with bondholders affected by financial sanctions recently imposed by U.S. President Donald Trump.
The president said he had given Vice-President Tareck El Aissami and Finance Minister Ramon Lobo "clear guidelines" for the negotiations, and some "bilateral conversations" with bondholders had already begun.
Last month, Trump, who brands Maduro as a "dictator," signed an executive order that prohibits Americans from dealing in new debt issued by the Venezuelan government or PDVSA.
That could complicate any possible debt refinancing attempt.
Julio Borges, the head of the opposition-led congress whose role has been overridden by the Constituent Assembly, has also been spearheading a campaign for foreign financial institutions to put the squeeze on Venezuela's government.
"I will be announcing Venezuela's definitive response to the financial aggression we - and the international investors - have suffered from Donald Trump and Julio Borges," Maduro said, adding that 74 percent of bondholders were American or Canadian.
"Venezuela will take a position to defend the judicial and financial security of the republic and its investors or holders of financial instruments," he added.
Maduro did not give more details of what his government wanted to discuss with bondholders or where talks would be held.
International reserves stood at $9.873 billion on Wednesday, at around the lowest level in at least two decades, according to central bank figures.
Most of the country's reserves are tied up in gold that cannot be used in financial transactions without going through a certification process in another country.
In the same address to the Assembly, Maduro said Venezuela would seek to "free" itself of the U.S. dollar and "implement a new system of international payments" using currencies such as the yuan, yen, rupee, euro and ruble.
The Venezuelan president did not, however, specify whether paying in a different currency was an option his government wanted to discuss with bondholders.
In an indication of financial strain with another creditor, Russian Finance Minister Anton Siluanov told reporters on Friday that Venezuela is having problems with fulfilling its obligations on its debt to Russia.
"We have a request from our colleagues in Venezuela to do a restructuring," he said. Venezuela owed Russia $2.84 billion as of September last year.
The OPEC nation is in the fourth year of recession, with its population grappling with triple-digit inflation and shortages of food and medicine. (Reporting by Deisy Buitrago, Corina Pons and Girish Gupta; Writing by Andrew Cawthorne; Editing by W Simon)