A deal by German drugs and chemicals giant Bayer to take over US seeds company Monsanto is imminent, media reports suggest.

The takeover would follow several months of talks and is thought to value Monsanto at more than $66bn (£50bn).

According to German media, Bayer has increased its offer to $129 per share while the Reuters news agency says the deal will be announced Wednesday.

The takeover would create the world's biggest seeds and pesticides company.

Combining Bayer and Monsanto would make it the market leader in the US, Europe and Asia.

Bayer's farm business produces seeds as well as chemicals to combat weeds and insects, but it is better known for its healthcare products such as Aspirin and Alka-Seltzer.

Monsanto is primarily known for its genetically modified seeds for crops including corn, soybeans, cotton, wheat and sugar cane. Such seeds have attracted criticism from some environmental activists.