But Boris Johnson said he would use the "firepower" of government to "put our arms around people" as it did during the coronavirus pandemic.
Mr Johnson was visiting Hilltop Honey in Newtown on Friday for his first public appearance since the Metropolitan Police said it had concluded its investigation into parties at Downing Street during lockdown.
He said reducing the cost of energy would be the main focus of his efforts to tackle the cost-of-living crisis.
"I'm not going to pretend to you that we can magic away every single expense that people are going to face as a result of a global spike in energy prices," he said.
"But be in no doubt that this will come down, we will get people through it. We will use the firepower we have built up to put our arms around people, just as we did during the pandemic."
Describing Wales as the "Saudi Arabia of wind power", Mr Johnson said refocusing the energy market away from imported oil and gas would be at the centre of reducing energy costs.
In the long-term this would mean investment in nuclear and alternative energy, but in the more immediate future it would mean making better use of the gas and oil reserves in this country.
He did not rule out lifting the moratorium on "fracking" for shale gas, but said there were also gas and oil reserves in the North Sea which could help alleviate the problem in the short term.
Mr Johnson said rural communities were particularly susceptible to rising fuel prices, and said the 5p cut in fuel duty in the Chancellor's Spring Statement should help with that.
He said he would look at what action could be taken against petrol companies which were not passing the cut on.
Mr Johnson said he was sceptical of the Welsh government's plans to tax second homes, saying reform of the planning process would be a better way to tackle the housing shortage.
"The best way to tackle that is to make sure we can develop affordable homes on brownfield sites," he said.
"Last year a record 400,000 people bought their own homes for the first time.
"The pandemic slowed down housebuilding, but we now need to speed it up again.
"I'm sure there are a lot of very good brownfield sites which could be used to build new homes given the right infrastructure. The important thing is to improve the planning system and get the infrastructure in place."
Mr Johnson said he would ask Chancellor of the Exchequer Rishi Sunak to look into calls for St David's Day on March 22 to be made a bank holiday.
Responding to this week's news that he would face no further action as the Metropolitan Police concluded its investigations into parties at Downing Street, Mr Johnson said he expected the Sue Gray report into the affair to be published next week.
He said Miss Gray would be under no pressure to suppress names in her final report.
"I'm very grateful to the Met for their work, I'm thankful for everything they've done," said Mr Johnson.
"We just need to wait for Sue Gray to report. Fingers crossed that will be very soon, and I'll be saying some more next week."