PRAGUE, April 10 - Russia must pull back its troops from the Ukrainian border as a first step to start dialogue over the crisis there, NATO General Secretary Anders Fogh Rasmussen said on Thursday, Reuters reported.

Rasmussen said some 40,000 Russian troops were massed along Ukraine's borders "not training but ready for combat."

He told a news conference during a visit to the Czech Republic, a NATO member, that any further military action by Russia would lead to grave consequences and severe economic sanctions.