The new Prime Minister has been urged to deliver a package of measures to help businesses in Northern Ireland hit by rising energy prices by Finance Minister Conor Murphy.
Speaking in Dungannon, the Sinn Féin minister said he'd heard first hand the difficulties facing businesses.
"Every day we hear of businesses left with no choice but to cease trading or to compress their opening hours in order to make savings on running costs," said Mr Murphy.
"The unpredictable, crippling energy bills facing our small businesses are not sustainable.
"For months I have been calling on the British Government to intervene to support businesses and their workers.
"Liz Truss must act now before it's too late for more businesses.
"The Westminster Government must step up and urgently deliver support which makes a real difference."
The finance minister said action should be taken to reduce VAT and duties on fuel and energy bills.
He added: "The reduced VAT for the hospitality sector must also be reinstated to assist these businesses, which were so adversely impacted by the pandemic.
"Given the ever-deepening crisis, more will need to be done to tackle the scale of energy bills expected over the winter months.
"It is essential that any package of measures put in place is delivered quickly to support our businesses and protect the jobs of those they employ."
It comes as another energy company announced it was increasing prices in Northern Ireland.
Click Energy, the smallest of five electricity suppliers in the region, said it was increasing prices by 28.2% at the start of October, affecting 26,000 customers.
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