Nalco has announced that it will be merging with Ecolab, a provider of cleaning, sanitising, food safety and infection prevention products and services.

The agreement has been unanimously ratified by the boards of both companies and will allow the firms to combine their expertise to achieve improved future growth performance, while expanding their capabilities.

Both organisations have identified the other's business model as being complementary, with the total value of the merger transaction having been placed at $8.1 billion (five billion pounds).

J Erik Fyrwald, Nalco's chairman, president and chief executive officer, said: "We are pleased to be partnering with Ecolab, a company we have long admired, and look forward to working together to realise substantial benefits for our shareholders, customers and employees."

This comes in the same week that Nalco reported record preliminary sales figures for the second quarter of $1.2 billion.

It also highlighted its progress last month in amending its pricing policy to account for the rising cost of raw materials.