Premier Oil gushes higher after reaching an agreement that will lift its drilling activities.It has agreed with Serica Energy that it will farm in to a 50% equity interest and assume operatorship of Block 22/19c in the UK Central North Sea.Iron ore producer Ferrexpo, which posted strong gains yesterday on the back of higher metals prices, is on the rise again today.FTSE 250 - RisersRank Group (RNK) 85.80p +6.92%Ferrexpo (FXPO) 225.50p +6.57%Premier Oil (PMO) 1,207.00p +4.14%Petropavlovsk (POG) 1,157.00p +4.14%CSR (CSR) 442.00p +3.80%Drax Group (DRX) 435.60p +3.71%Computacenter (CCC) 271.40p +3.59%Carpetright (CPR) 983.00p +3.31%Hargreaves Lansdown (HL.) 310.40p +3.26%Northern Foods (NFDS) 72.25p +3.21%FTSE 250 - FallersMelrose Resources (MRS) 280.00p -4.66%DSG International (DSGI) 36.70p -3.14%Daejan Holdings (DJAN) 2,906.00p -3.00%SVG Capital (SVI) 135.60p -2.87%Hunting (HTG) 596.50p -2.77%Filtrona PLC (FLTR) 188.80p -2.68%Misys (MSY) 217.10p -2.43%WH Smith (SMWH) 508.50p -2.40%Electra Private Equity (ELTA) 1,190.00p -2.38%Fidelity Special Values (FSV) 551.00p -2.22%