Tory MP Craig Mackinlay has launched a campaign for reform of "confused and sketchy" electoral law after being acquitted of expenses fraud.

He is urging MPs to back changes after a three-year court battle, which the prosecution said could have led to his election victory against Ukip's then-leader Nigel Farage being declared void.

Speaking in the Commons for the first time since the court decision, the South Thanet MP said: "It's surely unacceptable that innocent people are dragged through the courts at enormous expense to the public purse on the back of abstract law.

"The opportunity for ne'er-do-wells to get involved in election processes and cause prosecutions are surely obvious.

"Electoral Commission guidance is confused and it is sketchy. Surely it is in the interest of the House and all members that we have clear and unambiguous law, and I hope that a campaign for clarity in this area will be supported across this House."

Commons Leader Andrea Leadsom said she was "delighted" at his acquittal, adding: "My heart goes out to him for the difficult time he has had in recent years in clearing his name.

"It has become apparent from broader legal proceedings that election law on spending in 2015 was fragmented and unclear, with even the courts divided on the interpretation of the law.

"The Government will be taking steps to ensure there's a clearer and transparent framework in future elections working alongside the Electoral Commission.

"It's in everybody's interests that we get this right and the Government is committed to protecting and strengthening electoral integrity."

While Mr Mackinlay was acquitted in full, senior Conservative Party official Marion Little, 63, was convicted of falsifying election expenses in the same trial.

Little, who has worked for the party since 1974, was "carried away by her conviction" that defeating Mr Farage was an "overwhelmingly important political objective", a judge has said.

Prosecutors said more than £60,000 in staffing, hotels and advertising went undeclared in the battle for the Kent constituency, with Little said to have effectively run the Conservative campaign for the seat.

She was handed a nine-month suspended jail sentence and ordered to pay £5,000 towards the "very substantial" prosecution costs.

Trial judge Mr Justice Edis said the only reason she was not going to prison immediately was because she is caring for her husband, who is gravely ill with cancer.

Her conviction came after the jury was told "the law was simply abandoned" as the Tories set out to fend off the challenge of Mr Farage.

But a jury acquitted Mr Mackinlay of two charges of knowingly making a false election expenses declaration under the Representation of the People Act 1983 after deliberating for 53 hours and 29 minutes, having retired on December 5.