China Petrochemical Corp (Sinopec Group) is in talks with Repsol to buy the Spanish oil major's Argentine unit YPF even though YPF faces nationalisation, a Chinese financial news portal reported on Tuesday.

Citing a source close to Sinopec, Caixin.com said China's second largest oil company had reached a non-binding agreement to take over YPF for more than $15 billion.

Sinopec officials in Beijing were not immediately available for comment.

The report said Sinopec Group believed YPF's oil blocks in Argentina holds large development potential and it was confident that it can meet the Argentine government's requirement to accelerate development and production.

Argentine President Cristina Fernandez unveiled plans on Monday to take control of YPF, drawing swift warnings from key trade partners.

YPF has been under intense pressure from her centre-left government to boost production, and its share price has plunged due to months of speculation about a state takeover.

Repsol's chairman Antonio Brufau said in a news conference on Tuesday that the Spanish company had received lots of international interest in participating in YPF.

(Reporting by Charlie Zhu and Jim Bai, Editing by Jonathan Thatcher)