Hague condemns Syria repression
Britain will continue to work with its international partners to condemn the repression in Syria, Foreign Secretary William Hague has said.
Earlier, he said prospects of securing a UN resolution condemning the violence were "on a knife-edge".
Mr Hague said the violence was "unacceptable and must stop".
Protests against Syrian President Bashar al-Assad began in February and have spread across the country, with thousands fleeing into Turkey.
In a statement, Mr Hague said he remained "deeply concerned by the very serious situation in Syria".
"The Syrian government must allow immediate and unconditional access to the ICRC [International Committee of the Red Cross] and other humanitarian agencies. There is no excuse for denying this access," he said.
"We will continue to work with our international partners, including in the UN, to condemn the repression in Syria and call for the Syrian government to meet their people's legitimate demands."
Earlier, he told Sky News connections between Syria and its ally Lebanon made it "impossible" for Lebanon to take a clear position on the resolution.
Mr Hague also ruled out military action, saying there was "no prospect" of the UN authorising air raids.
The European Union and the US have warned Syria that government sanctioned violence was creating a humanitarian crisis.
But Mr Hague told Sky News' Murnaghan programme: "There is no prospect of getting through the UN a resolution such as the UN resolution 1973 on Libya.
"In the case of Libya there was a clear call from the Arab League for action, and that was a transformative intervention by the Arab League, there is no such call in the case of Syria.
"And indeed Lebanon is the Arab country that is represented on the UN Security Council at the moment, and the interconnections between the Lebanese government and the Syrian government have made it impossible for Lebanon to take a clear position on this, on the UN Security Council."
Mr Hague said Russia and China, who fear it could be the first step towards military intervention, had also strongly opposed the resolution.
The UK and France last week presented a draft UN resolution condemning Syria's suppression of protests.
Backed by Germany and Portugal, it condemns the systematic violation of human rights in Syria and demands an immediate end to violence, and access for humanitarian workers.
He said: "I do believe it is time for the security council to make a clear statement of the kind that we're advocating."
Meanwhile, International Development Secretary Andrew Mitchell told the BBC's Andrew Marr Show his department had been in touch with the International Red Cross about the humanitarian situation on the Turkish-Syrian border.
"Britain will give strong humanitarian support in terms of shelter and medicines and food, not least from our stores not too far away in Dubai.
"But the key thing is to stop the repression which is causing very large numbers of people to cross the border. If it continues, there could be an enormous exodus from Syria so we call on the Syrian government to stop this.
"Of course at the United Nations, Britain and others are seeking to get a resolution to put further pressure on the Syrian regime," he said.
Syrian government forces have continued to advance north as part of a widespread government crackdown, state media reports.
Human rights groups say more than 1,000 people have been killed since protests began in February against the rule of President Bashar al-Assad.