Is a civil marriage in Britain, without a guardian (wali), with the testimony of non-Muslims, and without seclusion (khalwa) except after its registration in the Egyptian real estate registry and the wedding ceremony, considered a legitimate (shar'i) marriage?

Marriage has pillars without which it cannot be validly contracted, namely: the presence of the woman's guardian (wali) along with two just witnesses, and a formula indicating the contract. The aforementioned marriage is invalid for several reasons:

1. It was conducted without a guardian (wali), which invalidates it according to the majority of scholars. 2. It was witnessed by non-Muslims, and the testimony of a disbeliever regarding the marriage of a Muslim woman is invalid by agreement of the four madhhabs (schools of thought). 3. The absence of the lawful formula for marriage.

Based on this, this marriage is invalid and must be annulled immediately. The man is a stranger (non-mahram), and the relationship is forbidden until the marriage is renewed with its aforementioned pillars.