Ali As-Sistani writes:

لا يجوز وطء الزوجة قبل إكمال تسع سنين، دواماً كان النكاح أو منقطعاً، واما سائر الاستمتاعات كاللمس بشهوة والتقبيل والضم والتفخيذ فلا بأس بها

,,Sexual intercourse with a wife is not permitted before the completion of nine years, whether it is a permanent or temporary marriage, but as for the rest of the pleasures, such as touching with lust, kissing, embracing and thigh intercourse, there is no problem in that.” [Minhaj-us-Salihin, Volume 3 page 10]

Abu l-Qasim Al-Khu’i writes:

لا يجوز وطء الزوجة قبل إكمال تسع سنين حرة كانت أو أَمة، دواما كان النكاح أو متعة

,,Sexual intercourse with a wife is not permitted before the completion of nine years, whether it is a free or a bonded marriage, whether it is a permanent or temporary marriage.” [Al-Mabani Fi Sharhi l-Urwati l-Wuthqa, Volume 2, Page 124]

وأما الاستمتاع بما عدا الوطء من النظر واللمس بشهوة والضم والتفخيذ فجائز في الجميع ولو في الرضيعة

,,As for enjoyment other than sexual intercourse, such as looking at her, touching her with pleasure, hugging her and thigh intercourse, all these are permissible, even if she were an infant.” [Al-Mabani Fi Sharhi l-Urwati l-Wuthqa, Volume 2, page 126]

Comment:

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Muhammad Sadiq Ar-Ruhani writes:

وأما خبر غياث بن إبراهيم عن جعفر عن أبيه عن علي عليهم السلام لا توطأ جارية لأقل من عشر سنين، فإن فعل فعيبت فقد ضمن فلهجره، ومخالفته لما تقدم، يحمل صدره على الكراهة إن أمكن وإلا فيطرح ومقتضى اطلاق النصوص عدم الفرق بين النكاح الدائم والمتعة وهل يجوز الاستمتاع بما عدا الوطء من النظر واللمس بشهوة والضم والتفخيذ؟ الظاهر ذلك ولو في الرضيعة للأصل السالم عن المعارض

,,As for the report of Ghayyath Ibn Ibrahim, who reported from Ja’far (a.) about his father (a.), that Ali (a.) said: ,,No one consorts with a young girl, that is younger than ten years old. If anyone were to do so, such that she is defiled, then he will be held accountable.” So this is to be avoided and is not in accordance with that, what has preceded. One interprets the expression of this as frowned upon, if this is possible and if not, then one rejects it. The obligatory expression of the texts states the nullity of the distinction between the marriage in permanence or in duration, but should the enjoyment such as the looking at, the touching with pleasure, the embracing and the thigh intercourse be allowed apart from the sexual intercourse? This is obviously the case, even if she were in infancy, since there is nothing fundamentally wrong with it.” [Fiqh-us-Sadiq, Volume 31 Page 139]

Ruhullah Al-Khumaini writes:

لا يجوز وطء الزوجة قبل إكمال تسع سنين دواما كان النكاح أو منقطعا وأما سائر الاستمتاعات كاللمس بشهوة والضم والتفخيذ فلا بأس بها حتى في الرضيعة

,,Sexual intercourse with a wife is not permitted before she reaches the age of nine, whether it be a permanent or temporary marriage. But as for the rest of the pleasures, such as touching with lust, hugging and thigh intercourse, there is no problem in that, even if she is in infancy.” [Tahrir-ul-Wasilah, Volume 2, page 221]