A senior Midland MP has admitted failing to tell an electoral watchdog about free long-distance flights donated by an offshore aviation company.
Caroline Spelman (Con Meriden), a member of the shadow Cabinet, visited Afghanistan and Kuwait in 2003 to learn about work to help children affected by war.
She registered free flights provided by a Bermuda-based company called Flying Lion in the Register of Members Interests, the official House of Commons register.
But under Parliamentary rules, she was also supposed to inform the Electoral Commission of all "gifts" over #1,000.
Mrs Spelman said she asked the Parliamentary Standards Commissioner, the official watchdog, for advice - and was told she only needed to register once.
She said: "There were no secrets. I listed the flights in the Register of Members Interests, which is a public document anyone can see.
"I didn't know I was supposed to declare them twice. But if I am, I will certainly do it.
"I have asked the Electoral Commission to explain to me what I need to do."
At the time, Mrs Spelman was shadow Secretary of State for International Development.
She visited Afghanistan to meet members of government and British and American forces, and to see the work of the Halo Trust.
This is a charity which clears up the debris of war, such as landmines and unexploded bombs, to try to make former conflict zones safe for local people, and in particular for children.
She also visited Kuwait to see children injured in the Iraq war. They included Ali Abba, who was orphaned and lost both arms when a missile hit his Baghdad home, and was later treated in Britain.
She worked with charity the Limbless Association to raise funds to help other children injured in the war.
Mrs Spelman is now shadow to the Deputy Prime Minister, responsible for local government issues.
Three other senior Conservatives also took flights with Flying Lion and failed to declare them with the Electoral Commission - Michael Ancram, a former deputy leader, Richard Spring, party vice-chairman responsible for business, and Mark Simmonds, a shadow Minister for International Development.
Birmingham Conservative Andrew Mitchell, the current shadow Overseas Development Secretary, made a full declaration to both the Commons and the commission. He has listed #12,300 worth of flights to Uganda, Mali and Rwanda.
The Government is proposing to remove the need for MPs to declare gifts with the commission.
Instead, it may expand the amount of information included in the Register of Members Interests to cover the addresses of donors and the value of gifts.
A Conservative Party spokesman said: "These MPs acted in good faith and registered the donation with the House of Commons authorities.
"It now appears the case that the donations should have been registered with the Electoral Commission as well. Any failure to double-report will be rectified. Parliament is currently planning to amend the law to remove the requirement to double-report."