Hi Preeti,
It is difficult to get the job (even short term contracts) even if you have a valid work permit and already relocated to UK. So forget about applying for these jobs from India and then migrating to UK. The situation here is very different than US where companies sponsor candidate's H1 visa. Ask me!
I have relocated to midlands area in the UK and trying to get the job desperately. I have a very strong J2EE background of 4.5 years and have a work permit (dependant on my husband and still eligible to work). However, companies here do not consider a strong experience of working in India. If you have already worked in UK then you have more chances to get to the interview. I have received many calls from the agents that they have really liked my CV and experience However, when it goes to the company, somehow the company do not seem to be considering it! Lets see what happens�
However, I am not sure about the job situation in London. Many of these sites list tons of jobs in and around London. So the companies there might consider sponsoring the work permit for candidate, but I am sure�cause that�s definitely not the case in midlands!
Regards,
Tejal