LONDON — Prime Minister Boris Johnson won a boost from Brexit supporters on Thursday as he marked one week until election day by setting out a plan for his first 100 days in office.

The Conservative leader appears increasingly confident of victory on December 12 as he remains around 10 points ahead of Jeremy Corbyn's Labour party in opinion polls.

The electoral threat posed by Nigel Farage's Brexit Party, meanwhile, receded further with the decision of four of its European Parliament MPs to endorse the prime minister.

Johnson has promised to get Britain out of the European Union on January 31, after years of turmoil sparked by the 2016 referendum vote for Brexit.

But he says this is only possible if he wins a majority of seats in the House of Commons next week, allowing him to get his EU divorce deal through parliament.

"2020 will then be the year we finally put behind us the arguments and uncertainty over Brexit," he said.

In a further enticement, he promised an unspecified tax cut for "hard-working families", which he said would be unveiled in a post-Brexit budget in February.

Within 100 days of taking office, he vowed to pass laws to increase school funding and toughen sentencing laws, as well as beginning moves to shake up the immigration system.

Late swing

Speaking to workers on a campaign visit to a factory in Derbyshire, central England, Johnson insisted he was leading a "new government, with a new approach".

But although he only took office in July, Labour questioned his promise of change, given the Conservatives have been in power since 2010.

"The Tories have had 3,494 days in office, and in those days we've seen child poverty soar, rising homelessness, rising food bank use, and violent crime is up too," said Labour's Andrew Gwynne.

The anti-Brexit Liberal Democrats, meanwhile, said the plan for government was "pure fantasy".

"A Tory government would remain completely consumed by Brexit not just for the next 100 days, but for years to come," said deputy leader Ed Davey.

Labour is offering a fresh referendum on Brexit but has sought to focus its campaign on a radical agenda to address inequality, from nationalising key industries to borrowing heavily to fund a huge investment drive.

Chris Curtis, political research manager at polling firm YouGov, said the Tories were heading for a "fairly comfortable majority" next week.

But he told AFP that a high degree of volatility in voting intentions "means that we shouldn't rule out a late swing towards one party or another".

Brexit Party fragmentation

Farage's Brexit Party has been nipping at the heels of the Conservatives for months, threatening to take EU referendum "Leave" voters from Johnson with its promise of a clean break with Brussels.

But the party has suffered a series of setbacks and four of its MEPs - elected on a huge show of support for the party in May's European elections - announced on Thursday they were backing the Conservatives.

Among them is Annunziata Rees-Mogg, the sister of Jacob Rees-Mogg who is a leading Brexit supporter and member of Johnson's cabinet.

She said the premier's EU divorce deal, which Farage has rejected as "Brexit in name only", would get Britain out of the EU and return its sovereignty.

"That is what most Brexiteers I've ever met have been fighting for decades," she told reporters.

With Labour backing a second referendum, she added that "Boris's deal is the only Leave option we have".

Farage said he was "disappointed" at the departures, the latest setback after he reluctantly agreed not to challenge Conservative MPs standing at the election.

But he says his Brexit Party is winning over voters in many traditional Labour areas of England, making it easier for the Conservatives to win there.

Len McCluskey, the head of the Unite trade union who is close to Corbyn, this week admitted Labour was struggling to win over Brexit-backing voters. — AFP