Methods of amplifying a target nucleic acid whereby the target nucleic acid is amplified in the presence of a deoxyribonucleotide triphosphate, a DNA polymerase having strand displacement activity, at least one chimeric oligonucleotide primer, at least one upstream block oligonucleotide and a RNase H; wherein the chimeric oligonucleotide primer contains a ribonucleotide positioned at the 3'-terminus; wherein the upstream block oligonucleotide is capable of annealing to a region 3' to a portion in the nucleic acid as the template to which the chimeric oligonucleotide primer anneals; and compositions and kits thereof.