Kings Cross to Smiths Square SW1P London - taxi or tube?

[hulahoopsilove]

I need to get from Kings X to Smith's Square in London (SW1P) have an hour and a bit to get there in a taxi as I will be carrying items...around 10.30ish is this possible do you think?

TFL says 35 minutes on the tube. I would go for a taxi if you have stuff to carry and would think that an hour would be masses of time.