The UK will give £50million in aid to Syrians after the fall of the Assad regime, Foreign Secretary David Lammy has announced.
The emergency support will be delivered through the UN and NGO agencies to people in the country, as well as to refugees in Lebanon and Jordan, the Foreign Office said.
Britain on Saturday joined talks in Aqaba, hosted by Jordan and attended by ministers and delegates from the US, France, Germany, the Arab Contact Group, Bahrain, Qatar, Turkey, the United Arab Emirates, the EU and UN.
They agreed on the importance of a "non-sectarian and representative government", protecting human rights, unfettered access for humanitarian aid, the safe destruction of chemical weapons, and combatting terrorism.
"The UK urges the transitional government to adhere to these principles to build a more hopeful, secure and peaceful Syria," the Foreign Office said on Sunday.
Some £120,000 of UK funding has also been made available to the Organisation of the Prohibition of Chemical Weapons (OPCW), the department said.
Another £30 million will be channelled within Syria for food, shelter and emergency healthcare, while £10 million will go to the World Food Programme (WFP) in Lebanon and £10 million to WFP and the UN's refugee agency, UNHCR in Jordan.
The intervention comes a week after the collapse of the Assad regime following a lightning offensive by rebel group Hayat Tahrir al-Sham (HTS).
Since then, Western governments have debated how to deal with HTS, which is a proscribed organisation in the UK because of its closeness to al Qaida.
Its current leader Ahmad al-Sharaa, who had used the alias Mohammed al-Golani before taking power, has attempted to distance his movement from the terrorist group.
There is also concern that a power vacuum in Syria could exacerbate regional tensions and create conditions for the so-called Islamic State group to regain ground.
Foreign Secretary David Lammy said: "The fall of the horrific Assad regime provides a once-in-a-generation chance for the people of Syria.
"We're committed to supporting the Syrian people as they chart a new course, first by providing £50 million in new food, healthcare and aid to support the humanitarian needs of vulnerable Syrians. Second, by working diplomatically to help secure better governance in Syria's future.
"This weekend the UK and its partners came together to agree the principles required to support a Syrian-led transitional political process. It is vital that the future Syrian government brings together all groups to establish the stability and respect the Syrian people deserve."
Sir Keir Starmer on Friday told a virtual meeting of the G7 leaders that "the fall of (Bashar) Assad's brutal regime should be welcomed but we must be cautious about what comes next".
In a statement on Thursday, the leaders said they were committed to "work with and fully support" a future Syrian government that agreed to ensure "respect for the rule of law, universal human rights, including women's rights, the protection of all Syrians, including religious and ethnic minorities, transparency and accountability".
