～と言いました vs ～とのことです


お忙しいところ、すみません。質問が２つあります。

In this sentence:

> 田中さんは「明日10時にまた電話します」と言いました。

Could it also be said as:

> 田中さんは明日10時にまた電話するとのことです。

Since when translated, they are both:

> Mr. Tanaka said that he will call again tomorrow at 10 o'clock.

Setting aside the aspects of being polite, is there other notable difference
between ～と言いました and ～とのことです when relaying something that was said?




The first sentence sounds unnatural as a sentence to relay someone’s message
to another person. It focuses on the fact that Tanaka-san, as the topic of the
sentence, said whatever he said, rather than its content.

The following sounds more natural.

> 田中さん **が** 「明日10時にまた電話します」と言 **っていました** 。

The second is good but it would also sound more natural with が, unless there
is some reason to put Tanaka-san's message in contrast with someone else's.

> 田中さん **が** 明日10時にまた電話するとのことです。

Of these two, the latter sounds more formal. It sounds like something a
secretary would say. The former could sound somewhat irresponsible, as if what
Tanaka-san was saying is someone else’s business.

