Lewis Hamilton says he expected a backlash from Spanish Formula One fans following his falling-out with former team-mate Fernando Alonso, but he has been shocked by the level of abuse he received on Saturday.

The McLaren driver, 23, was subjected to racist comments and was faced with a group of spectators wearing wigs, dark make-up and t-shirts with the slogan "Hamilton's Family" on the front during pre-season testing near Barcelona. And although the Briton insisted he still loves being in Spain, he admitted he was not prepared for what occured at the Circuit de Catalunya, in Montmelo.

"The truth is that I feel somewhat sad, I am in love with this country, and especially the city of Barcelona and this circuit, which is one of my three favourites," Hamilton said.

"The people in Spain have always been very warm with me, and even though I imagined what might happen it has not been pleasant.

"But maybe these types of things make you learn to appreciate more the warmth of the public, who although you always try to be there for them, you never know how important they are to you until these types of things happen."

Alonso has since joined Renault for the new season after a fractious 2007 partnering Hamilton during his rookie season.

"I would like [the Spanish fans] to understand my position," Hamilton said. "The only thing that I have done is to try to give the best of myself and try to win the championship. At no point have I tried to deliberately prejudice Fernando but the fight has been very tough and my image in Spain has been severely damaged."

McLaren have attempted to play down the problems but the sport's governing body, the FIA, have pledged to take a hard line on any future incidents.

"Vodafone McLaren Mercedes have raced and tested on Spanish circuits for many years, and everyone connected with the team regards Spain and the Spanish people with great affection, Lewis included," a McLaren statement said

The FIA, however, have warned that Spain could even be stripped of its grands prix as a result of such incidents, with the country due to host two races this year, at Barcelona and Valencia.

A spokesman said: "FIA are surprised and disappointed at the abuse directed at Lewis Hamilton. An act of this kind is a clear breach of the principles enshrined in the FIA statutes, and any repetition will result in sanctions."

The management at the circuit have also warned spectators about their behaviour. Ramon Pradera, the circuit director, added: "We would like to make a plea to the fans to behave correctly. No type of offensive behaviour can be tolerated."