BRUSSELS (Reuters) - The European Commission stands by the size of euro zone taxpayers' contribution of up to 130 billion euros ($169 billion) to the second Greek bailout, a Commission spokesman said on Wednesday.

International Monetary Fund Managing Director Christine Lagarde said earlier on Wednesday that Greece's public sector creditors may need to participate in restructuring its national debt if a haircut negotiated with private sector bondholders is not enough to make the debt load on Athens sustainable.

Asked to comment on Lagarde's remarks, the Commission's spokesman on economics and monetary affairs, Amadeu Altafaj, told a regular news briefing:

"The Commission's views have not changed in that respect, there is already a strong involvement of the public sector in the framework of the second programme for Greece."

($1 = 0.770 Euros)

(Reporting by Jan Strupczewski; editing by Rex Merrifield)