More than 130 Muslim scholars have written to Pope Benedict XVI and other Christian leaders urging greater understanding between the two faiths.
The Pope's remarks on Islam last year caused anger
The letter says that world peace could depend on improved relations between Muslims and Christians.
It identifies the principles of accepting only one god and living in peace with one's neighbours as common ground between the two religions.
It also insists that Christians and Muslims worship the same god.
The letter comes on the anniversary of an open letter issued to the Pope last year from 38 top Muslim clerics, after he made a controversial speech on Islam.
Pope Benedict sparked an uproar in September last year by quoting a medieval text which linked Islam to violence.
The letter coincides with the Eid al-Fitr celebrations to mark the end of Ramadan.
Koran and Bible
It was also sent to the Archbishop of Canterbury, the heads of the Lutheran, Methodist and Baptist churches, the Orthodox Church's Patriarch of Constantinople Bartholomew I and other Orthodox Patriarchs.
The letter, entitled A Common Word Between Us and You, compares passages in the Koran and the Bible, concluding that both emphasise "the primacy of total love and devotion to God", and the love of the neighbour.
With Muslims and Christians making up more than half the world's population, the letter goes on, the relationship between the two religious communities is "the most important factor in contributing to meaningful peace around the world".
"As Muslims, we say to Christians that we are not against them and that Islam is not against them - so long as they do not wage war against Muslims on account of their religion, oppress them and drive them out of their homes," the letter says.
It adds: "To those who nevertheless relish conflict and destruction for their own sake or reckon that ultimately they stand to gain through them, we say our very eternal souls are all also at stake if we fail to sincerely make every effort to make peace and come together in harmony."
One of the signatories, Dr Aref Ali Nayed, a senior adviser at the Cambridge Inter-faith Programme at Cambridge University, told the BBC that the document should be seen as a landmark.
"There are Sunnis, Shias, Ibadis and even the... Ismailian and Jaafari schools, so it's a consensus," he said.
Professor David Ford, director of the programme, said the letter was unprecedented.
"If sufficient people and groups heed this statement and act on it then the atmosphere will be changed into one in which violent extremists cannot flourish," he said in a statement.
The letter was signed by prominent Muslim leaders, politicians and academics, including the Grand Muftis of Bosnia and Hercegovina, Russia, Croatia, Kosovo and Syria, the Secretary-General of the Organisation of the Islamic Conference, the former Grand Mufti of Egypt and the founder of the Ulema Organisation in Iraq.