An increase in military and diplomatic activity between Russia and Belarus has led to fears a new front could be opened up in the war in Ukraine.
Russian President Vladimir Putin and Belarussian President Alexander Lukashenko are meeting on Friday almost a year after Belarus allowed Russia to invade Ukraine through its territory.
The northern invasion of Ukraine at the start of the war from Belarus put Kyiv under direct threat but months later Russia was forced into a humiliating retreat.
But now with an increase of Russian men and military equipment being noted in Belarus, there are fears Minsk could once again be preparing to get involved in the conflict.
What role has Belarus played so far in the conflict?
At the start of the war, Belarus allowed Russia to invade Ukraine from within its territory.
This allowed Russia to strike from the north directly towards Kyiv.
At the time Russia and Belarus believed it would be a quick conflict, with the Russian military planning on taking Kyiv in a matter of weeks.
This isn't what happened, which prompted Lukashenko to say in May of last year he did not expect the war to "drag on this way."
Because Belarus allowed the invasion to begin from its territory it has been hit with almost as many sanctions as Russia has.
For most of the rest of last year, Belarus played little role in the conflict after its initial support.
But recently more and more military cooperation between the two countries has led to renewed fears they may try and involve themselves again.
Who is Alexander Lukashenko and what is his relationship with Putin?
Alexander Lukashenko is the president of Belarus and has led the nation since the creation of the office in 1994.
The nation has elections but they are often criticised as being a sham, with Lukashenko earning the nickname "Europe's last dictator."
Throughout his time in office, he has sought to strengthen ties with Russia as much as possible.
This has led to close cooperation with Putin.
Although this has not stopped Lukashenko from occasionally criticising his neighbour.
In 2020 Lukashenko accused Putin of trying to make Belarus a part of Russia, which led to the first falling out between the two nations in years.
Belarus leans heavily on its Russian neighbour for economic and military support.
This closeness has only grown since the 2022 Belarusian election where the result was contested by opposition candidates.
The election led to large-scale protests, mostly by young Belarusians and people who wanted a closer relationship with the EU.
Lukashenko, with the backing of Russia, cracked down hard on the protesters and any free media in the country.
This left the country isolated from the west after the EU, UK and US condemned the situation and sanctioned Belarus.
Belarus's extremely close relationship with Russia has led to several rumours that the two nations might merge.
Belarus and Russia already have open borders with citizens from both nations allowed to live and work in the other country.
Many leading politicians in both countries, especially Russia, view Russians and Belarusians as the same people, with no ethnic or national distinction.
Putin used similar logic as one of his justifications for invading Ukraine, saying Ukrainians and Russians are one and the same.
This has long been rejected by most Ukrainian leaders and the majority of the population who often point to their two people's extremely difficult relationship during the 19th and 20th centuries.
Could Belarus get involved in the conflict?
There has been a lot of military activity in Belarus in recent months that has spooked Ukrainians about a repeat of last years invasion, but western analysts think it is unlikely.
Since the start of this year, Russia and Belarus have ramped up their joint military exercises.
The drills have seen Russian warplanes being stationed at Belarussian airbases.
Lukashenko has also given several indications that his country would help Russia if it needed it.
Last month he said: "If our Russian brothers need help, we are always ready to offer such assistance," during a visit to Zimbabwe.
But he insisted that Russia does not "need any" help.
Speaking to western journalists on Thursday Lukashenko said his nation would only join Russia if it was attacked by Ukraine.
He said: "I am ready to fight with the Russians from the territory of Belarus in only one case: If even one soldier comes onto the territory of Belarus to kill my people."
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Putin also made a rare trip abroad since the war started when he visited Belarus last month.
At the end of last year, a Ukrainian air defence missile landed in Belarus, but no damage to property or injuries were reported.
Belarus condemned the incident for which Ukraine offered to investigate.
Ukraine says it maintains troops on the Belarusian border and is constantly carrying out drone reconnaissance.
Western thought does not currently believe Russia and Belarus are planning a renewed offensive.
The Ministry of Defence said on January 11 that Russian aircraft and existing Russian troops in Belarus, though numerous, are "unlikely to constitute a credible offensive force."
The Pentagon has also said that it hasn’t seen any Russian troop movement in Belarus that would indicate an imminent attack.