Are there in the UK any particular regulations regarding sending business offers/requests by e-mail? I was unable to find any, but for example in my home country, Poland a company can send an e-mail asking for permission to send a business offer/request. The e-mail must only contain basic information about the company, such as the company name and the nature of business, as well as the name of the person who's sending the e-mail. Such an e-mail cannot contain any information about the company offers. Basically, I can write an e-mail to someone saying that I'm writing on behalf of my company that deals with something, and I'd like to grant their permission to send them my offer as I think they might find it interesting, or I want to cooperate with them. In such an e-mail I must not link to the company website, otherwise the e-mail would be considered spam.
Do you know of any similar laws applying to UK-based companies? Do you think that I could follow the Polish rules when I send e-mails to Poles on behalf of my UK company?
IANAL but AFAIK there is no rule such as you describe here in the UK.
However, everyone hates spam and it is very difficult to disguise an unsolicited contact as anything other than spam. Even if you get through the automatic spam filter on the email server, it is unlikely that this approach would succeed. For me, I'd consider it worse than spam, as it is either useless, or interesting, but doesn't include any details.
Cold-calling by sales people is an established business method, but most companies I have worked with are immune to even this, as they simply direct calls to voicemail and delete them, or pass the calls to the target's "assistant" who pretends to take a message, then never passes it on.