The average mortgage rate for a two-year fixed deal has risen to 6.01%, according to a financial information company.
Meanwhile, the average five-year fixed rate mortgage has increased to 5.67%, Moneyfacts said.
The two-year rate has risen from 5.98% on Friday, while the five-year deal has increased from 5.62%.
A two-year fixed deal is at a high not seen since 1 December - as the market reeled from Liz Truss government's botched mini budget.
Before then the rate had not reached the 6% mark since November 2008.
It comes as the prime minister declined to back extra support for mortgage holders despite higher interest rates making payments more expensive.
Asked if the government will introduce financial support for mortgage bills, similar to those introduced to help with energy bills, Rishi Sunak said he understood the public concern but his priority is to bring inflation down.
"I know the anxiety people will have about mortgage rates," Mr Sunak said.
"That's why the first priority I set out at the beginning of the year was to halve inflation because that's the best and most important way that we can keep costs and interest rates down for people.
"We've got a clear plan to do that. It is delivering. We need to stick to the plan."
Sir Keir Starmer ruled out direct mortgage support too and told Sky's Kay Burley show that Labour would "help people with their bills" with a higher windfall tax on oil and gas companies.
The Moneyfacts data also shows a drop in availability of mortgage products.
A total of 4,683 mortgages are on the market, down from 4,923 on Friday - but still more than the 3,890 on offer before the September mini budget of unfunded tax cuts and increased spending.
The Resolution Foundation think tank has said average annual mortgage repayments are set to rise by £2,900 for those renewing next year.
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