Tiny Rowland, the tycoon sacked by Lonrho last week, yesterday issued High Court writs against the company and against Dieter Bock, its chief executive.
The company faces a claim for damages for wrongful dismissal. Mr Rowland is also seeking redress for salary arrears, expenses and other benefits.
Mr Bock is accused of being in breach of an agreement governing the option he had to buy Mr Rowland's remaining 6 per cent stake in Lonrho.
Call-and-put options on the stake, whereby Mr Bock could demand to buy the shares or Mr Rowland could insist he bought them, were cancelled when Mr Rowland agreed to step down as joint chief executive of Lonrho in November. But there were doubts last night that the agreement was ever signed by either of the parties.
The shares are held in an escrow account at Credit Suisse, and Mr Rowland claims that Mr Bock is refusing to allow them to be released. Under the earlier agreement, the options can be exercised in December.
A spokesman for the company and for Mr Bock said both actions would be vigorously defended.
Mr Rowland's writ claims that continuing premption rights held by Mr Bock over the shares were invalidated when Mr Rowland ceased to be a director of Lonrho last week. It adds that Mr Bock has refused to give assurances to Mr Rowland's solicitors that he will instruct Credit Suisse to release the shares.
It also claims that last November's agreement included an obligation by Mr Bock to vote his shares in Lonrho in favour of Mr Rowland assuming the company's presidency at the annual meeting later this month.
The deal under which Mr Rowland,77, would retire from the board but become president was called off after last week's board meeting, at which Mr Bock mounted a final coup against the man who brought him into the company.
It was the culmination of a sporadic war between the two men, who were originally allies. Mr Rowland invited Mr Bock, a German property developer, into the company in 1993.
Mr Bock has since built up an 18 per cent stake, part of which he bought from Mr Rowland.
Mr Rowland's exit from the company last week ended a 34-year career at the head of the company during which he built Lonrho into an international trading empire with substantial interests in Africa.
Along the way, Mr Rowland, one of Britain's most colourful businessmen, often catapulted into the headlines with his famous feuds, such as his long-running struggle against the Fayeds over the takeover of House of Fraser, the group that owns the top people's department store, Harrods.