Spain's minister for education, culture and sport has urged supporters to bring an end to the booing directed at Barcelona defender Gerard Pique.
The former Manchester United man continues to be targeted by some fans during international matches, largely due to his support of Catalonian independence campaigns and some inflammatory remarks directed at Real Madrid.
Spain coach Vicente del Bosque hit out at fans who once more jeered Pique during Spain's 2-0 win over Slovakia at the weekend, while the proposed friendly with England in November has been moved from the Santiago Bernabeu to Alicante, with some reports in Spain citing treatment of Pique as key to the decision.
However, speaking to Radio Marca, Inigo Mendez de Vigo has hit out at supporters who refuse to back the players.
"It's very bad that a player who wears the national team jersey with pride should be booed," he said.
"You don't have to boo anyone. You have to respect, admire and love a player who wears the national team shirt.
"You have to respect the freedom of expression and others, and also respect those people. You can think what you want if you don't bother them.
"Anybody can disagree but you cannot show disgust because, ultimately, that's an attack on tolerance.
"Everyone - and I mean everyone - has to respect the symbols of a nation, the flags and the people. That is respect and education and that's what we have to teach our children."
Pique had also been criticised in some quarters after he was seen visiting a nightclub prior to the win over Slovakia, though Del Bosque later insisted he had been granted permission to go.
Spain take on Macedonia on Tuesday in their latest Euro 2016 qualifier.
