DUBAI: Some Western nations opposed to President Bashar Assad have discussed security cooperation with his government, Syria said on Wednesday, a move which if true would suggest a rise in Western concerns about foreign militants in rebel ranks.

The top U.S. and French diplomats both said they were personally unaware of such contacts but did not go so far as to deny that any had taken place.

Syria's Deputy Foreign Minister Faisal Mekdad said several Western intelligence services had visited Damascus for discussions. His comments were broadcast a day after the Wall Street Journal reported that French and Spanish spy services had made contact with Assad's government. French media have carried similar reports.

"I will not specify (which countries) but many of them have visited Damascus, yes," Mekdad said in a BBC interview.

Any suggestion that Western countries were talking to Assad's government could complicate their relationsips with opposition groups supported by the United States and Europe, and with wealthy Gulf states that fund the rebels.

Asked about the report, U.S. Secretary of State John Kerry indicated he was not aware of such contacts.

"I don't know anything about that. Certainly not under my auspices" had there been any contact of that kind, he told reporters in Kuwait, where he is on a visit.

In Paris, French Foreign Minister Laurent Fabius declined to comment, although when pressed he said he had the "same position" as Kerry. The defence Ministry declined to comment.

The French newspaper Le Figaro reported in December that the DGSE external intelligence service had gone to Damascus to discuss cooperation on terrorists. Damascus had replied that it would do so if France re-opened its embassy, it reported.

Britain's foreign office said it would not comment on intelligence matters. There was no immediate reaction from officials in Germany or Spain.

Western powers have long supported Syria's opposition with rhetoric but the past year has seen a shift in emphasis, with countries backing away from material aid to the rebels as al Qaeda-linked groups have gained power in rebel-held regions.

In September, the United States abandoned plans for missile strikes against Syria to punish it for using chemical weapons, putting an end to more than two years of speculation that the West could intervene against Assad as it did against Libya's Muammar Gadhafi in 2011.

In a deal brokered by Russia, Assad agreed instead to give up his chemical arms, a move that requires some degree of cooperation with Western countries to implement.

Western countries are worried about the presence in rebel ranks of foreign Islamist militants who have travelled to Syria to join a near three-year-old struggle to topple Assad.

"Frankly speaking the spirit has changed," Mekdad said. "Many of these countries have contacted us to coordinate security measures."

"When these countries ask us for security cooperation, then it seems to me there is a schism between the political and security leaderships," he added.

Assad has always maintained that the uprising against him is run by terrorists and that Western support for the rebels damages Western countries' own interests.

State news agency SANA reported on Wednesday that he had "warned that the danger of Wahhabi thinking has become a threat to the entire world and not just the region's countries," referring to the strict form of Sunni Islami embraced in Saudi Arabia and by many Sunni militant groups. Assad was speaking to the foreign minister of Iran, his main ally.

The uprising against four decades of Assad family rule erupted in Syria in March 2011. It descended into an armed insurgency after the army cracked down on protests.

On Tuesday the Wall Street Journal, citing diplomats and officials with knowledge of the situation, reported that French and Spanish intelligence agencies had been speaking to government officials in Damascus since November, traveling to Syria from Beirut.

British and French officials say hundreds of their citizens have fought in Syria with the rebels.

Of particular concern is the Islamic State in Iraq and Greater Syria (ISIS), an al Qaeda affiliate led by foreigners hardened by guerrilla warfare in Iraq, Chechnya and Libya.

A Free Syrian Army report prepared for the U.S. State Department and quoted by the Washington Post said the ISIS has a backbone of 5,500 foreign fighters, including 250 Chechens in Aleppo, and 17,000 recruited locally.

Recent weeks have seen other rebel groups, including Islamists, turn against the ISIS in fighting in which hundreds of people have been killed.