Theresa May not planning to extend UK military action in Syria
Theresa May has "no plans" to extend the UK's military action in Syria, her spokesman has said.
Bombing raids have been carried out against so-called Islamic State forces since December, but MPs voted against plans to launch air raids against President Bashir al-Assad in 2013.
Foreign Secretary Boris Johnson suggested earlier that more "kinetic" action might be under consideration.
But Mrs May's spokesman said every option came with "lots of issues".
Aleppo, once Syria's largest city and the country's commercial and industrial hub, has been divided roughly in two since 2012, with President Assad's forces controlling the west and rebel factions the east.
Air raids on civilian targets in the east in recent weeks have provoked outrage, with Russia, Assad's key ally, being widely blamed. It denies responsibility.
'No easy answer'
Questioned by the Commons Foreign Affairs Committee, Mr Johnson said: "Most people - I think including [US Secretary of State] John Kerry - feel that the process of discussion with the Russians has basically run out of road. On Sunday, we will be talking about all the options that we think are available to us and to the West."
Admitting there were was no "easy answer here" to stopping the bloodshed, he said: "Most people, I think, are now changing their minds about this and they are thinking 'We can't let this go on for ever, we can't just see Aleppo pulverised in this way, we have to do something.'
"Whether that means we can get a coalition together now for more kinetic action now, I cannot prophesy, but certainly what most people want to see is a new set of options."
The comments led to speculation that further military action was being discussed, despite the government losing a parliamentary vote on launching raids against Mr Assad in 2013.
Addressing Mr Johnson's comments. Mrs May's spokesman said: "Of course we are engaging with our like-minded partners, talking to them, continually thinking about what can be done to bring this conflict to an end.
"There are no plans for military action. We are working with the international community to look at how do we bring the conflict to an end.
"As the foreign secretary has said, lots of the options that people are looking at have got issues that would need to be addressed. But this is about continuing to look at them, continuing to work with partners, to look at how we can bring the conflict to an end.
"Ultimately we continue to believe that means a political transition in Syria and a political solution."
Mr Johnson has summoned a meeting of foreign ministers, including Mr Kerry as well as ministers from France and Germany, on Sunday to consider a new way forward in Syria and Iraq.
UK MPs have urged the government to consider establishing a no-fly zone over Aleppo, which would involve Western powers being prepared to destroy Russian and Syrian government planes and air defences.
Some MPs are pushing for a no-bombing zone instead, which could involve targeting runways and munitions stores and potentially using naval ships to launch missile attacks on helicopters dropping barrel bombs.
Earlier this week, Mr Johnson called for demonstrations outside the Russian embassy in London, arguing that "all the available evidence" pointed to its responsibility for the bombing of an aid convoy in Syria. Moscow accused him of "Russophobic hysteria".