By Lesley Wroughton
WASHINGTON (Reuters) - A U.S. sanctions team is in Europe this week discussing possible deeper sectoral penalties against Russia if a ceasefire deal with Ukraine is further violated, a senior State Department official said on Wednesday.
Victoria Nuland, U.S. assistant secretary of state for European affairs, told a congressional hearing there were new concerns about heavy shelling and fighting around Donetsk and on the road to Mariupol by pro-Russian separatists.
Another Russian convoy also had crossed the Ukrainian border, she told the House Foreign Affairs Committee.
"Our sanctions team is in Europe this week," Nuland said, adding that there had been more than 100 violations of the European-brokered ceasefire agreements.
She said it was important that the United States was in line with Europe on additional sanctions that will be imposed on Russia if the ceasefire worked out in Minsk last month is "further violated or if there is a further land grab."
Earlier, German Chancellor Angela Merkel warned Russia that any serious violation of the ceasefire, which she described as fragile, would prompt more sanctions.
The truce was agreed on Feb. 12 with Ukrainian President Petro Poroshenko and Russia's Vladimir Putin to end the fighting that has killed roughly 6,000 people since April.
Lawmakers on both sides of the aisle expressed frustration with what many said was the Obama administration's "resistance" to providing weapons to Kiev despite increased Russian aggression.
Representative Eliot Engel said he would propose legislation to support Ukraine and that while the United States was providing substantial assistance to Kiev, it was not enough.
"It will offer Ukraine greater assistance on a variety of fronts," Engel said. "It will dial up the pressure on Vladimir Putin for his reckless, destructive and destabilising policies."
Nuland said U.S. President Barack Obama was very engaged in the Ukraine crisis and had asked U.S. agencies for advice on arming Ukraine's military.
"These issues are still under review internally, including the types of equipment ... that would respond directly to some of the Russian supply," Nuland said, adding that Russia had transferred hundreds of pieces of military equipment to pro-Russian separatists since December.
Nuland acknowledged Ukraine had tried to acquire weapons on the world market but countries were waiting for the green light from Washington before they sold them to Kiev.
"A number of the things that the Ukrainians requested are not readily available unless the U.S. were to license onward export," Nuland said.