The mayor of Houston has called for the state of Texas to pay the huge electricity bills racked up by residents in last week's freezing weather.

Sylvester Turner told CBS News it was not the fault of residents that the system could not cope.

Some residents have reported bills in excess of $16,000 (£11,500) for a few days of usage.

Temperatures plummeted to 30-year lows, hitting 0F (-18C).

Much of Texas, which normally enjoys milder winter weather, was blanketed in snow.

The unusually cold weather across several southern US states claimed at least 70 lives.

Texas is recovering from the freezing temperatures, but many residents still have to boil water due to fears of contamination caused by low mains pressure.

Texas is one of the few US states to have an independent energy grid - so when the cold snap hit and power was in short supply, they were unable to receive support from neighbouring states.

As a result, the Public Utility Commission of Texas decided at an emergency meeting last Monday to raise the price of energy.

This change has not affected people on fixed-rate payment plans for their power. However, people on variable-rate tariffs - which can work out cheaper in the short-term, when weather conditions are consistent - have been hit hard by the increase and are now facing soaring costs.

Millions of Texans suffered power outages. Electricity supplies have largely been restored in the state, but just under 30,000 customers were still without power on Sunday afternoon, according to Poweroutage.us.

The Electric Reliability Council of Texas, which oversees the power system for most of the state, is being accused of not being prepared for the shortages.

Savings gone

Dallas resident and US Army veteran Scott Willoughby told the New York Times that he faced a $16,000 bill which had obliterated his savings.

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• How to stay safe in freezing weather

• In pictures: Snow blankets Texas

Mayor Turner told CBS that when he was in the state legislature, he had filed a bill to ensure there was "adequate reserve" to prevent blackouts, but it was not considered by the state's leaders.

The mayor of the country's fourth largest city suggested the system was not up to the challenges of storms produced by climate change.

"All of this was foreseeable. I wrote about it in 2011. And so for these exorbitant costs, it's not the consumers who should assume those costs.

"They are not at fault for what happened this week."