Reeves emphasised the importance of the next leader sticking to her fiscal rules, which include ensuring day-to-day spending is funded through tax revenue by the end of the Parliament and reducing debt as a proportion of GDP.
Burnham has previously committed to keeping the current government borrowing and spending rules in place.
“The last government lost control of the public finances,” Reeves said.
“It sent inflation through the roof and interest rates through the roof. So control of the public finances has a real impact on families today.”
While Reeves said she had improved the flexibility in the government’s budget by increasing its financial headroom, she added the public must be left in no doubt about the party’s commitment to fiscal discipline.
“Because if you lose control of the public finances, it is ordinary working people and businesses who pay the price with higher inflation, higher taxes and indeed higher interest rates,” she added.
The chancellor was absent from the crowd outside 10 Downing Street on Monday as Sir Keir announced he would be stepping down as prime minister, but was present for a group selfie with Burnham following his swearing-in at Westminster later the same day.
Reeves said no one could doubt her commitment to Sir Keir, but when pressed on her absence from his speech she would not be drawn on why she had not been present.
“I don’t think anyone can doubt my commitment to the prime minister. I’ve been by his side for six years now as shadow chancellor and then as chancellor of the exchequer,” Reeves said.
Reflecting on her time as chancellor so far, Reeves acknowledged there were things she could have done better but said she was “really proud” of her record which included increasing the national living wage and national minimum wage, and seeing the economy grow and inflation flatten out.
“I know that whoever is prime minister and chancellor in the future will inherit a stronger economy than the one I inherited two years ago,” she said.