Luiz Felipe Scolari, the Chelsea manager, has made it clear that Didier Drogba and Frank Lampard are firmly in his plans for next season despite speculation linking the pair with moves abroad.

Drogba stayed in London as Chelsea set off for their pre-season tour of China, but Scolari insisted the striker is recovering from a persistent knee injury. "Didier is injured and the doctor and our medical staff put together a recuperation plan for him and he will be out for three weeks, maximum four weeks," the 59-year-old Brazilian said. "It was impossible for him to come with us to China."

The Ivory Coast international's agent revealed last week that the 30-year-old will decide whether to sign a contract extension with Chelsea by Saturday. But Scolari is confident he will stay in London. "Didier's future is at Chelsea because he has a contract with us," he said. "I think he is happy at Chelsea. He will follow a normal recuperation plan and I hope when we come back he will be in good condition."

While Drogba recovers at Chelsea's Cobham training ground, Lampard made the trip to China with the rest of the squad, increasing hopes the England midfielder will at least stay at Stamford Bridge until the end of his contract, which runs out next summer.

"He is training every day in the morning and afternoon very well," Scolari said. "The most important thing is that he is here with us. I have spoken to him every day, we are talking every day about Chelsea, about what's the best way for Chelsea to play and when he is training with the other players what's the best position for him. I have spoken about how to win games with Chelsea and Lampard and no more."

Peter Kenyon, the Chelsea chief executive, echoed Scolari's words and insisted everything was still being done to secure Lampard's future, with Jose Mourinho, the Inter Milan and former Chelsea manager, looking to tempt the England midfielder to the San Siro.

"He is here and he is training exceptionally hard for us," Kenyon said. "He is a big pro and we are confident he will be with us next season.

"It is an important statement he is on tour with us and we have always said all along that we want Frank to stay and we are confident he will."

Claude Makelele and Khalid Boulahrouz will be allowed to leave Chelsea after the club agreed terms with Paris St Germain and Stuttgart respectively.