Prime Minister Boris Johnson’s Conservatives will complete Britain’s exit from the European Union by the end of January and hold a budget in February if they win the national election.

With a week to go until the December 12 vote that will decide the fate of Brexit and the world’s fifth-largest economy, the Conservatives lead the opposition Labour Party in opinion polls, but it remains unclear whether they are far enough ahead to form a majority government.

The Conservative Party has a 10-point lead over the opposition Labour Party, according to the Savanta ComRes poll published on Wednesday.

Setting out their plans for the first 100 days of government, the Conservatives pledged to ratify Britain’s EU exit, introduce new domestic law on issues such as health, justice and education, and set out tax cuts in a budget.

“This is the most important election in a generation – important because it will define if we go forward as a country or remain stuck, stalled, repeating the same arguments of the last three years with yet more damaging uncertainty,” Mr Johnson said.

“If there is a Conservative majority next week, we will get Brexit done by the end of January. 2020 will then be the year we finally put behind us the arguments and uncertainty over Brexit.”

Labour has promised to renegotiate the Brexit deal and hold a second EU referendum within six months.

If they win a majority, the Tories plan to set out their legislative program on December 19 and then – before Christmas – bring back the legislation required to ratify Mr Johnson’s EU exit agreement and pass it in time to leave by January 31.

The Conservative Party said it would then hold a post-Brexit budget in February “to take advantages of the opportunities provided by leaving the EU with a deal”, which would include tax cuts.

Finance minister Sajid Javid postponed a November 6 budget statement due to a delay to Britain’s scheduled October 31 EU exit and the government’s intention to hold an election.

The Savanta ComRes poll showed support for the Conservatives at 42 per cent, down 1 per cent compared with five days ago.

Labour was on 32 per cent, down 1 per cent, the pro-European Union Liberal Democrats were on 12 per cent and other political parties were on 15 per cent.