The United Kingdom announced Friday that it will soon reopen its embassy in Ukraine's capital, Kyiv.

The U.K. Embassy in Kyiv, in northern Ukraine, was forced to temporarily close in late February due to Russia's invasion. A contingent of British staff remained in western Ukraine to provide humanitarian and other support. U.K. Prime Minister Boris Johnson confirmed Friday that the embassy will reopen next week, "dependent on the security situation," according to a press release from the U.K. Foreign, Commonwealth and Development Office (FCDO).

"The extraordinary fortitude and success of President Zelenskyy and the Ukrainian people in resisting Russian forces, means we will shortly be re-opening our British Embassy in Kyiv," U.K. Foreign Secretary Liz Truss said in a statement. "I want to pay tribute to the bravery and resilience of the Embassy team and their work throughout this period."

The embassy premises in Kyiv are currently being made secure before staff return, starting with U.K. ambassador to Ukraine Melinda Simmons. The U.K. continues to advise its citizens against all travel to Ukraine, according to the FCDO.

-ABC News' Guy Davies

Russia's decision to blockade a steel plant in Mariupol "likely indicates a desire to contain Ukrainian resistance" in the strategic port city "and free up Russian forces to be deployed elsewhere in eastern Ukraine," the U.K. Ministry of Defense said Friday in an intelligence update.

The Azovstal Iron and Steel Works plant is the last holdout for Ukrainian fighters in besieged Mariupol.

"A full ground assault by Russia on the plant would likely incur significant Russian casualties, further decreasing their overall combat effectiveness," the ministry said.

Meanwhile, heavy shelling and fighting continues across eastern Ukraine's Donbas region as Russian forces seek to advance further toward settlements including Krasnyy Lyman, Buhayikva, Barvinkove, Lyman and Popasna, "as part of their plans for the region," according to the ministry.

"Despite Russia's renewed focus they are still suffering from losses sustained earlier in the conflict," the ministry added. "In order to try and reconstitute their depleted forces, they have resorted to transiting inoperable equipment back to Russia for repair."

Russian President Vladimir Putin will have a telephone conversation with European Council President Charles Michel on Friday before meeting with permanent members of the Russian Security Council, according to Kremlin spokesman Dmitry Peskov.

"Putin will now have an international conversation," Peskov told reporters Friday. "It will be the President of the European Council, Michel. And then during the day, Putin is scheduled to have an operational meeting with the permanent members of the Security Council."

Attorney General Merrick Garland announced Thursday during an unrelated news conference that U.S. and international allies have been in contact with Ukraine’s prosecutor general and is "helping in the collection of evidence and the preservation of evidence relating to possible war crimes."

Earlier this month President Joe Biden called Russian's killings of civilians a war crime and said Russian President Vladimir Putin needs to be held accountable.

-ABC News' Beatrice Peterson

Mariupol has not yet fallen, despite Russia's demands that Ukrainian troops defending the besieged Ukrainian port city surrender, according to Ukrainian Prime Minister Denys Shmyhal.

"There [are] still our military forces, our soldiers, so they will fight until the end," Shmyhal told ABC News' George Stephanopoulos in an exclusive interview Sunday on "This Week."

Mariupol is a strategic city for Moscow because it would allow Russian forces in the south to connect with troops in eastern Ukraine's contested Donbas region. It would also give Moscow a key port.

Although Mariupol remains under the Ukrainian government's control, Shmyhal said the city's residents are suffering.

"They have no water, no food, no heat, no electricity," he said. "They ask all of our partners to support and help stop this humanitarian catastrophe."

-ABC News' Monica Dunn