A delegation of MSPs is due to discuss Brexit legislation at the House of Lords in order to "avert a constitutional crisis".

Senior parliamentarians representing three Holyrood committees will set out cross-party concerns over the EU Withdrawal Bill on a visit to London.

They will attend the inter-parliamentary forum on Brexit, which brings together the relevant committees from both Houses of Parliament and the devolved legislatures.

It comes as the SNP slammed Scottish Conservative MPs for failing to "defend our national interest" by voting unanimously against amendments to the Bill in the Commons on Tuesday.

SNP Westminster leader Ian Blackford described the behaviour of the 13 Scottish Tory MPs as "utterly shocking" and said they had "promised Scots everything and delivered nothing".

A promise to introduce changes to the legislation's problematic clause 11 during report stage in the Commons failed to be met, with the amendments now expected to emerge in the Lords.

The UK and devolved administrations have been at odds for months on this key aspect of the Bill, which would result in EU responsibilities in devolved areas being temporarily transferred to Westminster.

The Scottish and Welsh Governments previously dubbed the Brexit legislation a "power grab" and have said they cannot recommend the devolved legislatures grant it consent in its current form.

The UK Government says the measure is necessary to avoid disruption of the UK's internal market and insists that it continues to make "good progress" in discussions with the Scottish Government.

Holyrood's cross-party finance and constitution committee has unanimously agreed that the current clause 11 is "incompatible" with the devolution settlement.

SNP MSP and committee convener Bruce Crawford said: "It is hard to overstate our concern, indeed dismay, that the UK Government did not amend the Bill during its Commons passage, despite a clear commitment to do so from UK ministers towards the end of 2017.

"If a constitutional crisis is to be averted, it is vital that the UK Government brings forward changes to the Bill that properly respect the devolution settlement."

He added: "All three of our committees welcome this chance to share our concerns with the Lords and appreciate their willingness to engage on issues that potentially endanger the devolution settlement."

Also joining Crawford as a delegate is Conservative MSP Graham Simpson, convener of the delegated powers and law reform committee.

He said: "My committee is strongly of the view that the Withdrawal Bill should be amended so that UK ministers can only legislate in devolved areas with the consent of devolved governments.

"At the same time, there needs to be a process for the Scottish Parliament to scrutinise Scottish ministers' decisions before that consent is given.

"Ministers will have extraordinary powers to make laws under this Bill, so it is vital that each of the UK's legislatures have the opportunity to scrutinise effectively regulations made under these highly unusual ministerial powers."

They will be joined by the SNP convener of the Europe committee, Joan McAlpine MSP, who said: "As the Bill approaches its passage through the Lords, this is a timely opportunity for us to raise again the concerns that my committee has highlighted on the implications of EU withdrawal for Scotland.

"As the House of Lords committees identified many similar concerns to us in their extensive work on Brexit, I hope that these joint discussions will feed into the consideration and scrutiny of the EU (Withdrawal) Bill by the Lords."

The other three in the delegation are the committees' deputy conveners Adam Tomkins of the Conservatives, the SNP's Stuart McMillan and Labour's Claire Baker.

A spokeswoman for the UK Government said: "Every part of the United Kingdom needs a functioning statute book, and that applies as much to Scotland as elsewhere.

"We have made good progress in our discussions with the Scottish Government on common frameworks and we look forward to making significant further progress over the coming weeks.

"We have made clear that we will bring forward an amendment to clause 11 of the Bill in the Lords, and are confident we can get to a position which has the support of all sides."