Deploying applications in federated clouds is becoming increasingly important. The ability to place application components in various locations is appealing to a large set of distributed applications. Components spread across a number of clouds still need to communicate with each other. Existing solutions for interconnecting clouds are using only single paths between sites, even though clouds typically have multiple up-links. This paper introduces our work on a MultiPath TCP (MPTCP) proxy suited for cloud interconnection. The proxy transforms TCP streams into multipath connections using MPTCP. By virtue of MPTCP, the bandwidth of multiple links is made available to the proxied connections and resilience can be improved without the need for additional fail-over mechanisms. The proposed solution works transparently for applications, making changes to existing applications unnecessary. Measurements of the implemented scheme confirm the additional throughput achievable and the gain in resilience.