The 21-year-old midfielder was one of the standout performers for Diego Simeone's side in an extraordinary 2013-14 season, which saw them claim the Spanish title and reach the final of the Champions League.
Barcelona president Josep Maria Bartomeu admitted he is a huge fan of Koke, who has been linked with Manchester United in recent months, but the Spanish youngster has stressed he is only concerned with earning a place at the World Cup at present.
"I have a long contract, I'm very happy. I'm proud to have important clubs interested in me, but I'm very happy here," he is quoted as saying by Marca.
"Right now I'm thinking as an Atletico player, I have the World Cup and I'm thinking of the present, not of the future.
"I got up this morning and several friends called me. On Saturday I'll be with the international coach, I'm not thinking of anything else.
"We had a spectacular season and there are important clubs who have come for our players. [CEO] Miguel Angel [Gil Marin] has already said we don't need to sell anyone.
"They are going to try to maintain this and to build a beautiful project."