Martial law, imposed in parts of Ukraine after Russia seized three of its naval ships in the Kerch Strait last month, was lifted on Wednesday, President Petro Poroshenko announced.
The emergency measure was put in place in 10 regions along the Black Sea and Ukraine's borders with Moldova and Russia.
It banned Russian men of combat age from entering the country, allowed authorities to ban public gatherings and put security forces, including reservists, on high alert.
Poroshenko said Ukraine's National Security and Defence Council would now discuss sanctions against Russia.
Twenty-four Ukrainian sailors are still detained by Russia following the incident on November 25 during which Russia seized two small Ukrainian armoured artillery vessels and a tugboat.
In a major escalation of tensions between the two countries, Russia accused Ukraine of illegally entering its territorial waters and blocked access to the Kerch Strait.
The narrow passage between the Crimean peninsula and Russia's southeast connects the Black Sea to the Sea of Azov and a 2003 treaty between the two countries stipulates they must cooperate on its use.
Ukraine denies the allegation and said it had informed Russian authorities of its plan to move the ships from the Black Sea port of Odessa to Mariupol in the Sea of Azov and reported that six of its military crew had been wounded.
Ukraine's Western allies including Britain, the US and NATO have called on Russia to release the Ukrainian ships and sailors but Russian President Vladimir Putin reiterated last week that they would face trial, insisting Ukraine deliberately provoked Russia.
A claim echoed by the Foreign Ministry on Wednesday which urged Ukraine's allies not to escalate tensions by taking part in any Ukrainian attempt to stage what it called "a provocation" near the Kerch Strait.
Ukraine said last week it planned to send warships to its Azov Sea ports via the Kerch Strait. Britain has also sent a Royal Navy ship to the area as a sign of support for Ukraine as "it faces illegal acts of aggression on its sovereign territory," British Defence Minister Gavin Williamson said on Twitter.
'Aggression in the Black Sea'
Poroshenko had announced earlier this month that he did not plan to extend martial law beyond its initial 30-day period unless Russia launched a large-scale attack.
But in a series of tweets on Wednesday, the Ukrainian President said the National Security and Defence Council would discuss sanctions for "the illegal elections in the occupied territory of Donbass and for the aggression in the Black Sea".
Donbass, in eastern Ukraine, has been the theatre of violent unrest between Russian-backed separatists and Ukrainian forces since 2014 when the Ukrainian revolution started and Crimea was annexed by Russia.
Poroshenko also suggested on Wednesday that turning away "more than a thousand Russian citizens who failed to justify the purpose of their travel to Ukraine" when they attempted to cross into the 10 regions under martial law had led to "26% fewer crimes in the past month than usual".