MEXICO CITY, March 31 (Reuters) - Mexico's state oil company Pemex will sell up to 5 billion pesos in three to seven year debt on the local market on Wednesday, IFR, a Thomson Reuters publication, reported.

Pemex has been expected to issue local debt since it filed a shelf authorization with Mexican securities regulators to issue up to 70 billion pesos in debt at the beginning of March.

The final size of the deal is still being determined, IFR reported. Pemex is expected to issue a three-year floating rate note linked to the local TIIE benchmark interest rate and a seven-year fixed rate note.

The heavily-indebted company may issue up to $10 billion in debt this year to refinance its existing liabilities and partially fund this year's $19.4 billion capital spending plan.

Pemex chief executive Jesus Reyes Heroles said the company could add up to $3 billion to its debt load this year after reducing liabilities the last two years.

The company sold a $2 billion 10-year bond in January but was forced to pay a substantially higher coupon than in the past due to the global credit crunch. (Reporting by Robert Campbell)