MADRID - The European Central Bank has no power to control rising mortgage costs that are having a particularly harsh impact on Spanish citizens as a result of its interest rate increases, ECB President Christine Lagarde said on Thursday.

In Spain around three-quarters of the population are homeowners, with most opting for floating-rate mortgages that are exposed to more aggressive interest rate rises.

For a variable 25-year mortgage loan of 100,000 euros ($106,160), the monthly cost was 196 euros higher in February than a year earlier, according to the Spanish consumer association Asufin.

"We are the protectors of the euro, mortgages are not for the ECB to decide," Lagarde told Spanish TV channel Antena 3 when asked about a recent proposal by the far-left junior ruling coalition partner Unidas Podemos to cap mortgage loans and moderate banks' profits.

"It is not our mission," she added.

In November, the government introduced mortgage relief support for more than one million vulnerable households, but Spanish parties are promising more help to woo voters ahead of regional and national elections later this year.

Lagarde's remarks come at a time when the two biggest Spanish banks Santander and BBVA have reported record profits in 2022. But while lenders benefit from higher rates on loans, Spanish banks have kept a lid on increases in interest on deposits, pushing savers into higher-yielding short-term government debt.

On Thursday, Lagarde said savers were right to expect better remuneration for their deposits.

"If we deposit our savings and are prepared to leave them there, negotiations should start between the customer and the banker so that these savings are remunerated," Lagarde said.

Spanish one-year bank deposits paid on average 0.42% in interest as of December, compared to the 1.34% euro zone average, according to ECB data.

"Bank customers have to have this dialogue with bankers and if not, switch banks," Lagarde said.

($1 = 0.9142 euros)

(Reporting by Jesús Aguado and Emma Pinedo in Madrid, additional reporting by Francesco Canepa; editing by Tomasz Janowski)