US senators urge arms for Ukraine

Leading American senators have called for the US to send weapons to help Ukraine fight what they say is "a Russian invasion," the BBC reported.

Robert Menendez, head of the Senate Foreign Relations Committee, said Russia's President Vladimir Putin must face a cost for his "aggression."

Senator John McCain said: "This is not an incursion. This is an invasion."

Earlier, Mr Putin called for talks to discuss the matter of "statehood" for eastern Ukraine.

Meanwhile, a meeting of the so-called Contact Group on Ukraine is expected to start later on Monday in Minsk, Belarus.

Representatives of Ukraine, Russia and the Organization for Security and Co-operation in Europe will attend the talks. The participation of pro-Russian rebels from eastern Ukraine remains unclear.

Last week's first direct talks between Mr Putin and Ukrainian President Petro Poroshenko in Minsk did not lead to any major breakthrough.

The pro-Russian separatists have been gaining ground on Ukrainian forces in recent days, in both the Luhansk and Donetsk regions, and further south around the port of Mariupol.