Under-Pressure Johnson Makes His International Debut In Ukraine.

Boris Johnson's trip to Ukraine was a change of theme and location for him.

For a few hours on Tuesday, the political challenges of the previous few days could be forgotten, and the more serious issues of European security could take their place.

He came to Kyiv to convey his support for a country under siege, a place where political survival has a more visceral, existential meaning, far removed from Westminster's inflated analogies.

Mr Johnson assured his Ukrainian counterpart, Volodymyr Zelensky, that the United Kingdom will always defend his country's independence.

He promised him £88 million in aid and sent a clear warning to Moscow: if even a single Russian toe cap crossed the border, they would be confronted by a determined Ukrainian army "a terrible and ferocious resistance I believe that Russian parents and moms should consider this."

Mr Johnson also warned Moscow that any economic sanctions imposed on as a result of the invasion of Ukraine would be "automatic."

As a result, the message was clear: strong support for Ukraine and strong deterrent for Russia.

The question is whether this message was moderated by Mr Johnson's domestic political preoccupations, which are being keenly monitored by diplomats throughout the world.

While President Macron of France has been having regular phone contacts with President Putin, Mr Johnson's call with the Russian leader on Monday was postponed due to the Downing Street argument about lockdown parties.

Indeed, despite policy disagreements, one of the most notable parts of this crisis thus far has been how much the West has managed to hold together with a unified message.

Mr Johnson faces challenges, the new German government is settling in, Mr Macron is facing a tough election battle, and the United States has a president whose tongue occasionally slips.