The Marine Accident Investigation Branch (MAIB) is still investigating the blaze on Wight Sky three months after it occurred.
The ongoing probe means the Maritime and Coastguard Agency has imposed wind restrictions on the vessel, causing widespread disruption to services from Yarmouth to Lymington.
In a letter to Nus Ghani, Bob said: “The slow progress of this investigation is having a significant adverse impact on the service which Wightlink provides to my constituents.
“Until this investigation is concluded – and the resulting recommendations are implemented – Wightlink will continue to suffer from service disruption, particularly because of wind restrictions that MCA has placed on the operator in the meantime.
“There has been another fire this weekend which has had a major impact, leading to an even tighter wind restriction being put in place by the MCA.
“I would therefore seek your urgent intervention as the relevant minister, to require MAIB to accelerate and conclude its investigation as a matter of urgency.
“It is unacceptable for such a lifeline service, which many of my constituents rely on for hospital, commuter and personal commitments, to be continually and repeatedly disrupted as a result of the slow progress of MAIB’s investigation. The outcome of this investigation is needed in order for the issue to be fully resolved.”