British Prime Minister Boris Johnson told his new cabinet of ministers they had a momentous task ahead and were committed to delivering Brexit by October 31 during the team's first meeting on Thursday.
"We have a momentous task ahead of us. At a pivotal moment in our country's history we are now committed, all of us, to leaving the European Union on October 31 or indeed earlier, no ifs, no buts," he said at the start of the meeting.
He is also expected to make a statement to parliament on his priorities for government on Thursday, the office of the leader of the House of Commons said on Twitter.
Johnson, who officially took over Britain's top job from Theresa May on Wednesday, sets the world's fifth largest economy up for a showdown with the EU and a potential constitutional crisis - or election - at home, as lawmakers have vowed to thwart a no-deal Brexit.
Britain's new leader promised to do a new Brexit deal with the bloc within less than 99 days but warned that if EU leaders refused - what he termed a "remote possibility" - then Britain would leave without a deal, "no ifs or buts".
"I am convinced that we can do a deal," Johnson, 55, said on arrival at No. 10 Downing Street, the premier's official residence, after meeting Queen Elizabeth who requested he form a government.
Johnson's bet is that the threat of a no-deal Brexit will persuade the EU's biggest powers - Germany and France - to agree to revise the divorce deal that former Prime Minister Theresa May agreed last November but failed to ratify.
The EU has so far repeatedly refused to countenance rewriting the Withdrawal Agreement part of the divorce deal but has said it could change the so called "Political Declaration" on future ties.
The bloc has congratulated Johnson on his victory but was firm that it would not offer Britain better departure terms.
Brexiteer-dominated team
Johnson, who sported a sometimes shambolic persona in his rise to power, showed mettle in office, sweeping away his predecessor’s government in one of the biggest culls of senior government jobs in recent British history.
A total of 17 ministers in May's government either resigned or were sacked, creating a powerful new group of enemies in parliament.
Most of Johnson's senior appointees are Brexit supporters.
Sajid Javid, 49, was named as his finance minister. He is a euroskeptic who voted to remain in the 2016 referendum.
Others are avowed Brexiteers: Priti Patel was appointed interior minister, Dominic Raab was appointed foreign minister and Stephen Barclay remained as Brexit minister.
Johnson also appointed Dominic Cummings, the campaign director of the official Brexit Vote Leave campaign, as a senior adviser in Downing Street.
'We want an independence referendum'
Scotland's nationalist leader warned Johnson that she would continue preparations for an independence referendum because his Brexit plans would hurt the Scottish economy.
"It is now - more than ever - essential that in Scotland we have an alternative option," Scottish First Minister Nicola Sturgeon said in a letter to Johnson.
"The Scottish government will continue to make preparations to give people in Scotland the choice of becoming an independent country," she said, adding that the Scottish parliament would consider framework legislation for a referendum after the summer recess.
(With input from Reuters)