Kalou is understood to have agreed a new four-year deal to join Didier Drogba, Ashley Cole and John Terry in pledging his future to the Blues.

The Ivory Coast international's contract was set to expire at the end of the season but Chelsea moved quickly to tie the striker down on a longer contract after FIFA imposed a transfer ban on the club.

The Blues are prevented from signing any new players for the next two transfer windows after being found guilty of inducing teenager Gael Kakuta to breach his contract with Lens two years ago.

Chelsea have appealed against FIFA's ruling but the Kalou deal represents another timely boost for the club should they fail to get the verdict overturned.

Kalou's deal is reported to be worth around £60,000 a week to the 23-year-old, who reached the World Cup finals with the Ivory Coast when they drew 1-1 with Malawi at the weekend.

Kalou's club and country colleague Didier Drogba now wants to his country to make history in South Africa next summer.

"It is going to be a challenge," said Drogba, who scored against Malawi. "To make it to the final will not be easy because there are great teams like Brazil and Germany who have won the World Cup for many years.

"But my team-mates and I want to make history and want to change the way the world sees African football. We will do everything we can to get to the final and hopefully win the competition."

Meanwhile, Germany captain Michael Ballack has given Chelsea a massive boost after revealing his ankle injury is not as bad as was first feared.

The Chelsea midfielder sustained the problem in a first-half collision with Blues team-mate Yuri Zhirkov during Germany's 1-0 qualifying win in Moscow.

The victory ensured Germany's place in the finals next summer and Ballack quickly refuted suggestions that the injury would rule him out for a significant period.

He will be fit enough to play against Aston Villa on Saturday and could even figure in Germany's clash with Finland on Wednesday.

"It is not that serious as we had thought," said Ballack. "During the match it was pretty much aching, but afterwards it was not. It is pretty fine now though.

"I believe I could be ready for the match on Wednesday as thankfully it was not a big thing."