Web monitoring firm Websense is warning of a major phishing attack on European banks, possibly because they have weaker security.

The company discovered attacks against over two dozen European banks over the weekend, primarily against Spanish and Italian institutions.

This is the first time that Websense has witnessed such a concerted attack against European banks. US sites like Citibank and PayPal are more usual targets.

"We're seeing a move to find the weakest link," said Mark Murtagh, EMEA technical director at Websense.

"Bigger banks have made some strides in providing material to prevent phishing but some are still relying on just a user name or password.

"Interestingly The Netherlands rarely gets targeted because almost every bank there has two-factor authentication or uses one-time passwords."

Murtagh explained that phishers are increasingly targeting small non-English banks, which were formerly left alone because they have fewer users.

But Websense is now seeing more attacks against Spanish banks, since it is the fourth most widely spoken language in the world and offers access to customers in Europe and South America.

"The Dutch are hit less and have two-factor authentication, but the two aren't necessary linked," said Sandra Quinn from the Association for Payment Clearing Services. "The real reason could be that Dutch is quite difficult to speak."

She pointed out that language is often a big stumbling blocks for phishers. Early attempts at phishing failed miserably when poor language skills left phoney bank emails easy to spot.