Labour MP urges probe into Philip Hammond's Yemen answers
Chancellor Philip Hammond is facing calls for a Commons motion of contempt over answers he gave to Parliament on Yemen when he was foreign secretary.
Labour's Ann Clwyd has urged action after the Foreign Office amended statements and answers to questions about the conflict in the country.
In his original answer, Mr Hammond said the Saudi Arabian-led coalition's actions complied with humanitarian law.
But the Foreign Office later said it had not done any relevant assessments.
The government said errors in Mr Hammond's statement and other similar answers given by other Foreign Office ministers between January and June were not a deliberate attempt to mislead Parliament.
The UK and US have been supporting Saudi Arabia and nine other Arab nations who have been fighting rebels who seized power from the Yemeni government in 2015.
The coalition has been accused of war crimes in a number of incidents, including an airstrike on a Medecins Sans Frontieres hospital in the capital Sa'ana.
In a written statement issued in January, Mr Hammond said the UK treated allegations that the coalition had violated international humanitarian law very seriously but "our judgement is that there is no evidence that IHL has been breached".
But a correction issued on 21 July said that Mr Hammond should have stated that "looking at all the information available to us, we have been unable to assess that there has been a breach of IHL by the Saudi-led coalition".
Ms Clwyd said the discrepancies in Mr Hammond's statement and those issued by other ministers were serious and she wanted to know whether the UK's approach was influenced by the fact that it was a major exporter of arms to Saudi Arabia.
She has asked the Commons Speaker John Bercow to refer the matter to the Committee of Privileges to consider whether Mr Hammond and other ministers have been in contempt of Parliament by deliberately misleading MPs.
"For some time, Saudi Arabia - using British bombs and planes - may have committed war crimes on Yemeni civilians," she said.
"UK arms sales to Saudi Arabia topped £3.3bn in the first year of the Saudi-led conflict in the Yemen. We need to know the truth."
In a statement, the Foreign Office said: "The clarifications ensure consistency with numerous other Parliamentary responses and in no way represent a change in policy.
"The UK continues to monitor the conflict in Yemen closely and relevant information gathered from that monitoring is taken into account as part of the careful risk assessment for the licensing of exports to Saudi Arabia."
The UN is currently trying to broker a ceasefire in the long-running conflict in Yemen, with talks taking place in Kuwait.