By Jesús Aguado MADRID (Reuters) -Senior executives at Spanish lender Bankinter said on Thursday a proposed tax on Spanish banks to help tackle the rising cost of living could hit capital levels, hurt economic growth and dent investor confidence in the sector. The Spanish government is holding a meeting with banks on Friday to discuss a planned 3 billion euro ($3.1 billion) levy on lenders. Bank of Spain governor Pablo Hernandez de Cos is also expected to attend to basically focus on the economic situation, said two sources with knowledge of the meeting. The proposed taxes add uncertainty that…