The Government today criticised Channel 4's decision to broadcast an Alternative Christmas Message by Iranian president Mahmoud Ahmadinejad.

The Foreign and Commonwealth Office (FCO) said the invitation by the broadcaster to the hard-line leader would cause international offence.

An FCO spokeswoman said: "President Ahmadinejad has during his time in office made a series of appalling anti-Semitic statements.

"The British media are rightly free to make their own editorial choices, but this invitation will cause offence and amusement not just at home but amongst friendly countries abroad."

The decision to allow Ahmadinejad to deliver the Alternative Christmas Message tonight has already angered human rights campaigners, Israelis and politicians.

Mr Ahmadinejad's anti-Western rhetoric and views on Israel and homosexuality have strained international relations between Iran and the West.

The broadcast is not scheduled at the same time as the Queen's Speech on BBC and ITV as in previous years, but will go out at 7.15pm.

Campaign groups attacked the broadcaster's decision to air the speech, as "dangerous" and motivated by ratings.

However, the president uses the message to express his wish for a peaceful New Year and greater spirituality among governments, leaders and society as a whole.

Speaking in Farsi with English subtitles he will say: "Jesus, the Son of Mary, is the standard bearer of justice, of love for our fellow human beings, of the fight against tyranny, discrimination and injustice.

"If Christ were on earth today, undoubtedly He would stand with the people in opposition to bullying, ill-tempered and expansionist powers."

But the Israeli Embassy branded the Christmas message a "sick and twisted irony".

Israeli Ambassador Ron Prosor said: "In Iran, converts to Christianity face the death penalty. It is perverse that this despot is allowed to speculate on the views of Jesus, while his government leads Christ's followers to the gallows."

He said Channel 4's decision to broadcast the message was a "scandal and a national embarrassment" and in "its search for ratings and shock factor, Channel 4 has lost its ethical way".

Louise Ellman, Labour MP for Liverpool Riverside and chairwoman of the Labour Jewish Movement, also blasted Channel 4.

She said: "I condemn Channel 4's decision to give an unchallenged platform to a dangerous fanatic who denies the holocaust while preparing for another and claims homosexuality does not exist while his regime hangs gay young men from cranes in the street.

"Who will deliver next year's alternative Christmas message? Will it be David Irving or Robert Mugabe?"

Human rights campaigner Peter Tatchell joined the attack, and called on the broadcaster to "pull the plug on this criminal despot, who ranks with Robert Mugabe, Omar al-Bashir of Sudan and the Burmese military junta as one of the world's most bloody tyrants".

Stephen Smith, director of the Holocaust Centre, said the message should be treated with caution.

President Ahmadinejad's views on the state of Israel and his claims that the Holocaust is a "myth" have angered Jewish groups.

Mr Smith said: "I think this benign message is deceptive. People need to be alert to the fact that this is a wolf in sheep's clothing.

"Many of his political and historical views are very dangerous and do not uphold the views in his message."

Rabbi Aaron Goldstein, of Liberal Judaism, said: "I have no trouble with Channel 4 dealing with difficult issues. The Queen's speech is so benign that it is worthwhile having something thought-provoking.

"But doing a sort of lucky dip to pick out a controversial character, then allowing him to make a lovey-dovey speech, that this character is being allowed to dress himself up as a kind of Father Christmas, that is problematic."

However, Channel 4 received support from Ben Summerskill, director of gay rights group Stonewall.

He said: "In spite of his ridiculous and often offensive views, it is an important way of reminding him that there are some countries where free speech is not repressed."

This is not the first time the channel has courted controversy with its choice of speaker. In 2006 a fully-veiled British-born Muslim woman used the message to attack Jack Straw for his criticism of the niqab (face veil) earlier the same year.

It is the broadcaster's 16th alternative message since Quentin Crisp delivered the first in 1993.

Channel 4 head of news and current affairs Dorothy Byrne defended the decision to broadcast tonight's message.

She said: "As the leader of one of the most powerful states in the Middle East, President Ahmadinejad's views are enormously influential.

"As we approach a critical time in international relations, we are offering our viewers an insight into an alternative world view.

"Channel 4 has devoted more airtime to examining Iran than any other broadcaster and this message continues a long tradition of offering a different perspective on the world around us."

Shadow foreign secretary William Hague said: "The invitation to President Ahmadinejad from Channel 4 is bizarre and ill-judged.

"He is known internationally for his defiance of the international community over Iran's nuclear programme, and his government at home presides over repeated human rights abuses.

"To choose him for a Christmas Day message gives the false impression he has a ready audience for his views and is insulting to the people of Britain."