SNP bosses are today expected to finalise the selection of candidates to stand in the five Westminster seats in Scotland not currently held by the party.

It is understood business convener Derek Mackay has told members contenders should be appointed soon after nominations close at 5pm today.

Usually Westminster and Holyrood election candidates are elected by members in a ballot, but Mackay has said such a process would take about 70 days and the tight timescale for the June 8 vote meant candidates would be appointed by him and the national secretary Dr Angus MacLeod.

The SNP currently hold 54 of Scotland’s 59 seats and the party have given the go-ahead for sitting MPs to stand again. SNP MP hopefuls are being selected in Edinburgh West, Edinburgh South, Glasgow East, Dumfriesshire, Tweeddale and Clydesdale, as well as Orkney and Shetland.

Jim Eadie, the former MSP, is expected to be put forward by members to challenge Ian Murray in Edinburgh South. He will be up for selection against activist Doug Thomson as well as Lee-Anne Menzies, who works for MSP Ash Denham.

In Edinburgh West sitting MP Michelle Thomson is standing down. Thomson was elected as an SNP MP but currently sits as an independent. Activists Toni Giugliano, Jamie Szymkowiak and councillor Louis Ritchie are expected to be considered.

David Linden, who works for MP Alison Thewliss, is the probable frontrunner for Glasgow East, while Professor Donna Heddle is understood to be the likely challenger to the LibDem’s Alistair Carmichael.

It is not clear who will be vying to stand against Tory MP David Mundell. The SNP’s Emma Harper has ruled herself out. She came within 728 seats of unseating him in May 2015 before being elected to Holyrood last year. SNP MSP Joan McAlpine is a possible contender.

Tory MSP John Lamont yesterday announced he will stand down at Holyrood to focus on the fight in Ettrick, Roxburgh and Berwickshire. The seat is the most marginal for the SNP, with Lamont being defeated by the SNP’s Calum Kerr by just 328 votes in 2015.

Lamont will step down from Holyrood with effect from May 4, with Presiding Officer Ken Macintosh expected to set the date for a by-election shortly.

He said it had been “a great privilege” to serve as an MSP for the last 10 years and pledged to continue to “put local people before party politics” if elected as an MP.

“This is one of the most important General Elections Scotland has ever had,” Lamont said.

“In the Borders, it will be a straight fight between myself and the SNP.

“I have decided to stand down as an MSP to allow me to focus all of my energy on this important contest and to ensure that the electorate have a clear choice between the two contenders.

“I’ve taken this decision because I believe that I am best-placed to help increase the number of Scottish Conservative and Unionist MPs at Westminster so we can stop the SNP bandwagon in its tracks.

“With this decision, no-one can doubt my commitment to representing the Borders to the best of my ability.”