What is the ruling on a husband's right to cohabitation (Qasm) and conjugal rights (Wat') when traveling due to an excuse or necessity?

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The husband's right to the wife's time allotment (Qasm) and the right to sexual intercourse (Wat') are suspended when the husband travels due to a valid excuse or necessity. This principle applies even if the journey is prolonged. Furthermore, the marriage contract of a missing person whose wife is left without financial support (Nafaqah) is invalid.