Petrol and diesel prices could rise within days due to the plunge in the value of the pound, according to experts.
Brian Madderson, chairman of the Petrol Retailers Association, said a rise of 2.5p per litre would be expected if the US dollar continues to trade at around 1.35 to the pound.
"I would think certainly by early to middle of next week we'll see prices moving upwards", he added.
In a statement issued on Friday, the AA also predicted an increase in prices: "Assuming that current market conditions persist over the next 10-14 days, the price of petrol at some fuel stations might be expected to rise by 2.25p a litre or £1.25 a tank."
The FTSE 100 Index has closed 2.7% down, equating to more than £45 billion being wiped off the value of the UK's biggest companies, after Britain voted to leave the European Union.
The FTSE recovered from a 7% plunge following David Cameron's announcement that he would quit as Prime Minister by October following the Brexit vote.
The UK economy is "resilient" to the impact of the EU referendum vote, G7 finance ministers and central bank governors have said.
They said steps had been taken to "ensure adequate liquidity and to support the functioning of markets" and that they were ready to use "established liquidity instruments to that end".
"We affirm our assessment that the UK economy and financial sector remain resilient and are confident that the UK authorities are well-positioned to address the consequences of the referendum outcome," they said in a statement.
"We recognise that excessive volatility and disorderly movements in exchange rates can have adverse implications for economic and financial stability.
"We remain united and continue to maintain our solidarity as G7."
Financial services firm Morgan Stanley has denied rumours it is planning to move 2,000 investment banking jobs to Frankfurt and Dublin after the EU referendum vote.
Sources earlier told the BBC that the process was already underway.
The Dow Jones Industrial Average plummeted more than 400 points as global markets descended into chaos following Britain's vote to leave the European Union.
Major banking and financial services firms BNP Paribas and JPMorgan are considering moving their London bases to Paris, according to reports.
ITV News understands the firms are considering the move following the EU referendum result.
The International Monetary Fund (IMF) has urged the UK and EU to ensure a "smooth transition" to a new economic relationship after the Brexit vote.
Christine Lagarde, managing director of the IMF, said it strongly supported the Bank of England and ECB's commitments to "supply liquidity to the banking system and curtail excess financial volatility".
She said: “We urge the authorities in the U.K. and Europe to work collaboratively to ensure a smooth transition to a new economic relationship between the UK and the EU, including by clarifying the procedures and broad objectives that will guide the process.
“We will continue to monitor developments closely and stand ready to support our members as needed.”
British Airways owner IAG has issued a profit warning after British voters chose to leave the European Union.
It came as the company's share price fell 19% to 425.6p.
"Following the outcome of the referendum, and given current market volatility, while IAG continues to expect a significant increase in operating profit this year, it no longer expects to generate an absolute operating profit increase similar to 2015," the company said in a statement.
The firm insisted it believes the vote "will not have a long-term material impact on its business", but added that it experienced "a weaker than expected trading environment" in the run-up to the referendum.
Economists have started to downgrade their forecasts for UK growth, predicting Britain could head into recession unless a quick deal can be done.
IHS Global Insight said it is "substantially cutting" its GDP growth forecasts to 1.5% from 2% for 2016 and to 0.2% from 2.4% for 2017.
Capital Economics downgraded its forecast for 2016 from just above 2% to 1.5%.
Fitch said the vote for Brexit will be "credit negative for most sectors in the UK", triggered by "weaker medium-term growth and investment prospects and uncertainty about future trade arrangements".