The Government is increasing its work with the Syrian political opposition as part of efforts to create an alternative to President Bashar al Assad's regime.
Foreign Secretary William Hague said a British diplomat met representatives of the Free Syrian Army (FSA) this week.
The UK will also provide an extra £5m in non-lethal equipment - including mobile phones, satellite phones, and radio equipment - to help activists co-ordinate efforts.
At a news conference at the Foreign Office, Mr Hague said: "This will help protect unarmed opposition groups, human rights activists, and civilians from some of the worst of the violence."
Questioned about whether weapons should be supplied, he said that was a "much more difficult decision".
He stressed there had been reports of atrocities on the opposition side too, adding: "If we were to do that, it would be very difficult to know how that equipment would be used."
Sky's foreign affairs editor Tim Marshall said it represented a shift in strategy by the UK government, and a move to broker relations with the people who were likely to be in power in a post-Assad scenario.
He said the new communications equipment would "inevitably end up in the hands of men with guns".
Meanwhile, rebels retreated from the key Aleppo district of Salaheddin under heavy shelling, as a veteran Algerian diplomat was set to be named the new international envoy to Syria.
"We have staged a tactical withdrawal from Salaheddin. The district is completely empty of rebel fighters. Regime forces are now advancing into Salaheddin," said Hossam Abu Mohammed, an FSA commander.
"A large number of civilians were killed, as were some 40 rebels. Forty buildings have been flattened."
Syrian state television said: "Our special forces have cleansed Salaheddin district of terrorists."
It came as Algerian diplomat Lakhdar Brahimi, 78, is to be named as Kofi Annan's replacement as Arab League joint special envoy for Syria, according to diplomatic sources quoted by Reuters news agency.
Mr Assad's forces have so far killed more than 15,000 people, in its effort to crush the rebellion that erupted in March 2011, some Western leaders say.
Damascus said rebels have killed several thousand members of its security forces.
Mr Annan, a former UN secretary-general, announced last week he would step down because he was unable to do his job with the UN Security Council's veto powers deadlocked over Syria.
The council united in April to approve the deployment of 300 monitors to observe a failed ceasefire as part of Mr Annan's peace plan.
But Russia and China have vetoed three other resolutions criticising Syria and threatening sanctions against Damascus.