1999 clio probs

hi guys, i have a 1999 1.2 clio tried to start it, but had nothing so i jump started it....now this happens,i jump start it it turns over,( in neutral) but it revs at just over 5k,it will not stop unless i dip the clutch and place into gear, at this time still 5k revs,only when i release the clutch to the bite it stops and revs return to normal, once clutch is dipped revs return to 5k,drove up road and it has not stopped even when slowed to park. as i said it only stops revving when clutch at the bite... any ideas would be grateful guys