Chancellor George Osborne will seek to reassure financial markets on Monday morning following Britain's decision to leave the EU.
Mr Osborne will make an early morning statement setting out how the Government intends to move forward and "protect the national interest" after the referendum result.
It comes after turmoil across the political spectrum, with Prime Minister David Cameron announcing he is to resign and Labour leader Jeremy Corbyn facing a wave of resignations from his shadow cabinet.
Mr Osborne will speak before the markets open in a bid to head-off a repeat of the run on the pound and global stock market plunge which was provoked by the unexpected Brexit vote.
"The Chancellor will make a statement to provide reassurance about financial and economic stability in light of the referendum result and the actions that he and the rest of the Government will be taking to protect the national interest over the coming period," a Treasury spokesman said.
The Chancellor is also under pressure to set out a timeline for opening negotiations with the EU on the terms of Britain's "divorce" from the EU.
Mr Cameron has insisted his successor should be the one to invoke article 50 of the Lisbon Treaty which sets in train formal withdrawal procedures after he leaves Downing Street in October.
But EU leaders are unimpressed with this proposed delay as they insist the UK has opted to quit and needs to be out of the bloc as soon as possible.
Mr Osborne will also need to clarify whether he will try to bring-in the so-called "punishment Budget" comprising of £30 billion worth of tax rises and spending cuts that he insisted during the referendum campaign would be necessary in the event of the UK voting for Brexit.