The companies behind Call of Duty and World of Warcraft are merging in a deal which could shake up the global video games industry.

Activision and Blizzard have said they will form "the world’s most profitable games business" in a deal worth $18.8bn (£9.15bn).

US-based Activision also makes hit console games such as the Tony Hawk series and Guitar Hero.

Nine million people pay a monthly subscription to play World of Warcraft.

’High-growth industry’

Blizzard is the biggest player in online gaming and World of Warcraft is the global market leader of what are known as massively multi-player online role-playing games, or MMORPGs.

It is currently owned by the French media group Vivendi.

As part of the merger plan, Blizzard will invest $2bn in the new company, while Activision is putting up $1bn.

The merged business will be called Activision Blizzard and its chief executive will be Activision’s current CEO Bobby Kotick. Vivendi will be the biggest shareholder in the group.

Jean-Bernard Levy, Vivendi chief executive, said: "This alliance is a major strategic step for Vivendi and is another illustration of our drive to extend our presence in the entertainment sector.

"By combining Vivendi’s games business with Activision, we are creating a worldwide leader in a high-growth industry."