The Everton manager says that the young midfielder is prepared for the World Cup.
But the Spaniard emphasised that pressure on the player should be kept to a minimum.
In an interview with Press Association Sport, Martinez said: “You can never get an experience like playing in a World Cup too soon if you are ready and Ross is ready.
“What is important is, as a nation, we have a responsibility to look after a young man who goes to the World Cup with the only intention of helping England be as good as they can.
“He is still young and we have to protect him. If we protect him well we are talking about a potential world-class talent.
“But it is down to us to allow him time and a little bit of a path to fulfil his potential with England.
“We shouldn’t expect Ross Barkley, at the age of 20, to go into a World Cup and be someone who has to win games single-handedly. That would be very wrong.”
