Translation:I cannot answer the phone right now.
I can't attend the phone right now. .. is wrong. Should that be the case?
I've heard people say that, but it really should be "attend to" and not simply "attend".
a general rule of thumb is to avoid contractions in english. DL doesn't seem to like them
I can't come to the phone just now. Or I can't answer the phone right now. NO English speaker would say 'attend to the phone'!
It might not be the common way to say it "attend to the phone" - but there is nothing incorrect - and there do exist people who would us the phrase - but it is a rather formal thing. For exemple the boss is getting a call, but he does not want to answer - he instruct his secretary: Tell Mr. so and so that I cannot attend to the phone right now.