MPs are calling on the Government to provide extra funding to help strengthen the region's railways against severe weather.
In a letter signed by eight cross-party South West MPs, Nick Harvey and Geoffrey Cox called on the Government to make a further £31 million available for immediate flood resilience work.
It follows the recent harsh weather which has caused major damage to rail routes throughout the South West, cancelling dozens of services in and out of the region.
Writing to the Secretary of State for Transport, Patrick McLoughlin, the group said: "Securing the investment needed for Network Rail's flood resilience programme for the South West is the urgent priority and a necessary first step in a campaign to deliver the transport infrastructure and services vital to the South West's future economic security."
Speaking separately on the issue, Mr Harvey said recent events had highlighted the vulnerability of the region's railways.
He said: "The recent severe weather flood damage to our railways in places like Dawlish has underlined the vulnerability of the South West's rail network.
"Rightly, people in North Devon are becoming increasingly worried about how easily we can become cut off from the rest of the country during severe weather events. It's time the Government grasped the urgency of the situation."