Here's a typical exchange ( at least in the UK): Person A: Excuse me. Person B: (as they step out of the way) Sorry. Person A: Thanks. Person B: (That's) OK. Note that Person B probably just mumbles their side of the conversation. Also note that saying 'Sorry' does not necessarily mean that you've done something wrong. You may have every right to be standing or sitting where you are, and you'll still say 'Sorry'. It's not an apology as such, but more of an acknowledgement of a slightly uncomfortable situation. In fact, Person A might also use 'Sorry', as in 'Sorry to bother you'. This is particularly the case with the classic situation of having to disturb the passenger sitting in the aisle seat of an aircraft. A typical way of alerting your neighbour to the fact that you want to leave your seat is moving as if to get up and saying 'Er, sorry, could I just...um.....', and by that point they will have got the message. At least this applies to the ultra-apologetic Brits, and possibly the equally polite Canadians, too.

Hi, Paritosh. In England we often just make a very English-sounding noise. Something like 'oop'. But, also in very British fashion, you could just apologise with 'I'm sorry' and move out of the way.

Hi Paritosh, In American English we might say, 'go ahead' or 'after you' or 'no problem' with an open hand gesture. Some people might even include 'sir' at the end. As in, 'go ahead sir', 'after you sir', or 'no problem sir'. Although it would also be normal for an American to say 'excuse me' or 'excuse me sir', as they do in England.