Ukrainian authorities say modern jets are needed to help the country regain control of the skies, but allies have been hesitant so far, fearing they will antagonise Russia and escalate the conflict.
Both the United Kingdom and the United States have ruled out sending F-16 fighter jets to Ukraine.
It is “not practicable” to send them to Ukraine to help it battle Russia, according to Downing Street.
While US President Joe Biden said “no” when asked if he would send F-16s to the frontlines, he reaffirmed that Washington will not hand Kiev any of the planes.
It comes as Ukrainian officials increased their appeals for allies to give modern warplanes to allow them to manage their airspace.
There are concerns that sending such technology could escalate the conflict and be interpreted by Russia as NATO members intervening in the fight through proxy.
The prime minister’s official spokesman said on Tuesday: “The Typhoon and F-35 fighter jets used by the United Kingdom are incredibly advanced and require months of training to fly. Given this, we believe that sending those jets into Ukraine is impractical.
“We will continue to give and accelerate military assistance to Ukraine, as well as carefully consider their requests.
“The time it takes to learn how to use what are highly complex pieces of technology is the limiting factor in this case, but we will look into what else we can do to help Ukraine.”
Britain’s defence secretary indicated on Monday that he was keeping an open mind about joining any future alliance that supplied jets.
Ben Wallace told parliament that there was a history of governments claiming they would not transfer guns but then changing their minds.
France’s President Emmanuel Macron has not ruled out the possibility, but has stated that specific criteria must be met.
When Ukraine’s defence minister visits France this week, he is expected to make his case for planes.
According to Ukraine’s top presidential adviser, there have also been “good signs” from Poland.
The current appeal for jets comes after Western allies agreed to provide dozens of tanks to the conflict last week.
America and Germany stated they would hand up more than 40 prisoners, in addition to the 14 committed by the United Kingdom and the 74 pledged by Poland.
However, it is expected that it would be several months before some of them are delivered and ready to fight.
Despite the fact that billions of pounds in weaponry and small guns have already been provided to the country, Ukraine has stated that modern tanks are essential for pushing back Russia and reclaiming territory.