US anti-trust regulators are close to filing a complaint against chip maker Intel over uncompetitive practices in its microprocessor and chip set businesses, according to a Reuters report.

The Federal Trade Commission (FTC) opened an investigation into Intel last year, and it is now thought that three out of the four commissioners on the case are in favour of filing a complaint, including FTC chairman John Leibowitz.

"They're close," one source is reported as saying. "They said it could be a matter of weeks or a matter of months when the vote happens."

If the FTC files against the chip giant, it will follow Europe, Japan and South Korea in moving for anti-trust violations. The European Commission said in May that Intel had violated European anti-trust standards and levied a £948m penalty against the company.

However, Intel has maintained that it will appeal against the ruling, repeatedly contending that EU investigators did not fully analyse the evidence, and that the Commission did not possess an accurate picture of the state of the semiconductor market.

Commenting on the FTC speculation, Intel spokesman Chuck Mulloy said that he believed the firm's business practices were lawful.

"We certainly have been working closely with the FTC as they conduct their investigation. We would hope that the speculation is incorrect as we are continuing to work with the Commission," he told Reuters.