LONDON (Reuters) - Prime Minister Boris Johnson is set to clash with lawmakers in parliament this week over his plans to take Britain out of the European Union with or without an exit deal, a showdown that could see Brexit delayed and the government toppled.

FILE PHOTO: The Houses of Parliament can be seen as a man walks along the South Bank in London, Britain, August 30, 2019. REUTERS/ Henry Nicholls

That has raised the chances of an early parliamentary election, before the next scheduled vote in 2022.

An election can be triggered in two ways:

1. JOHNSON CALLS AN ELECTION

If Johnson decides parliament is intent on thwarting his plan to deliver Brexit on Oct. 31, he could try to call an election, seeking a majority that would allow him to push his plans through.

He would need to put the proposal for an election to parliament and win a two-thirds majority in the 650-seat legislature.

The opposition Labour Party has long called for an election, so there should be enough votes to support holding one, although Tony Blair, a former Labour prime minister, has warned it would be an “elephant trap” for the party that it should avoid.

If successful, an election could be held in mid- to late-October, before the Brexit deadline.

The law states there must be 25 working days between an election being formally called and polling day, which is traditionally a Thursday. Therefore an Oct. 17 election is possible if the steps have been taken by the end of Sept. 12.

2. NO-CONFIDENCE VOTE

The opposition Labour Party can call a no-confidence vote in the government.

If a majority of lawmakers back the no-confidence vote, then it sets off a 14-day period where either an alternative government can be formed and take control without an election or the government can win back power. If neither an alternative government nor the existing government can win a confidence vote within this period, an election is called.

There are legal restrictions setting out a minimum period before an election can take place after the government loses a no-confidence vote, but not on the maximum period before one needs to be held.

This raises the possibility that Johnson could set the election date after the Oct. 31 Brexit deadline.

The law around the 14-day period is untested and there is likely to be disagreement over who has the right to try to form a government and whether the prime minister is duty bound to resign.