For collision handling between shortened Transmission Time Interval (sTTI) and Transmission Time Interval (TTI) transmissions, a method determines a collision between user equipment (UE) uplink transmission resources in a first TTI 16 of a first TTI length and uplink transmission resources in a second TTI 16 of a second TTI length. The method further transmits a first uplink data transmission block (TB) in the first TTI and a second uplink data TB in the second TTI. The method interrupts the transmission of the first uplink data TB before transmission of the second uplink data TB. The method receives an indication that indicates whether to resume transmission of the first uplink data TB. The method determines to resume the transmission of the first uplink TB based on the indication.