Five Ukrainian servicemen seriously wounded in fighting with pro-Russian separatists will be treated in a British hospital, British Foreign Secretary Philip Hammond announced Sunday.

Nobel peace prize winners on Sunday expressed deep concern about the growing threat of conflict, including nuclear war, and "a new and more dangerous Cold War."

U.S. Secretary of State John Kerry arrived in Rome on Sunday for a flurry of meetings about a looming showdown at the United Nations amid a European-led drive to push moves towards Palestinian statehood.

U.S. officials told reporters accompanying Kerry on his plane that Washington wanted to learn more about the European position, saying the U.S. administration had not yet decided whether to back or veto any U.N. resolution on the issue.

The U.S. Congress on Saturday unanimously approved fresh economic sanctions against Russia and lethal weapons for Kiev, defying President Barack Obama and hardening American lawmakers' response to a Kremlin-backed insurgency in Ukraine.

Identical texts of the Ukraine Freedom Support Act passed both the Senate and House of Representatives on Thursday, but because of a technical issue it returned to the Senate where it passed by unanimous consent moments before the chamber adjourned late Saturday night.

The Ukrainian army on Saturday reported 11 attacks against its positions in the east where a ceasefire is tentatively holding and said a drone was spotted over Mariupol, the last major eastern town under its control.

"The surveillance activities of the enemy have intensified around Mariupol where a drone was identified," the military said in a statement.

Russian Deputy Prime Minister Dmitry Rogozin, who oversees defense, said Saturday that Ukraine was its own worst threat, after Kiev announced plans to boost its armed forces because of the conflict in east Ukraine.

Rogozin quoted Ukrainian Defence Minister Stepan Poltorak as telling parliament Friday that Kiev faced threats both from pro-Russian separatists in its east and also from the pro-Russian separatist region of Transdniestr on its southwestern border.

Russia responded angrily on Saturday to news that U.S. senators had passed a bill calling for fresh sanctions against Moscow and the supply of lethal military aid to Ukraine.

"Undoubtedly, we will not be able to leave this without a response," deputy foreign minister Sergei Ryabkov told Interfax news agency ahead of a meeting between the Russian and U.S. foreign ministers.

Top U.S. diplomat John Kerry will meet with his Russian counterpart Sergei Lavrov in Rome on Sunday amid a toughening American response to a Kremlin-backed separatist insurgency in Ukraine.

Russian deputy foreign minister Sergei Ryabkov said Saturday that "an agreement has been reached on a meeting between Russian Foreign Minister Lavrov and U.S. Secretary of State John Kerry in Rome on Sunday," cited by Interfax.

Ukraine on Friday cheered the passage of a U.S. Senate bill allowing Washington to provide lethal military assistance to the embattled country for its fight against Russia-backed rebels.

Norway announced Friday it is extending a freeze in military cooperation with Russia until the end of 2015 because of its neighbor’s role in the Ukrainian crisis.